HINTS AND SUGGESTIONS ON NETS, BREEDING-CAGES, Etc.

As some difficulty is experienced in Teneriffe by persons who arrive there without already being provided with materials for collecting Lepidoptera, the description of a few useful expedients resorted to may be of service. A moderate knowledge of the Spanish language is a very useful help towards obtaining any small necessaries, but the Spanish shop-keepers are most obliging, and understand quickly by the help of a very few words what is wanted.

A butterfly-net is one of the first requisites, so some wire must be bought at the tin-smiths, of whom there are several in Orotava. With a little instruction he will make it into a ring about one foot in diameter, with a socket of tin soldered on to it. Into this socket an ordinary walking-stick can be fixed for a handle. The stick is useful to walk with over the rough ground when not required for the net, and the net can be easily carried with other necessaries one has to take on an expedition.

Mosquito-netting answers the purpose of green gauze for the net. Gauze is the best, however, and can be purchased in England, but not in Orotava. The mosquito-netting gets soft and pliable by use, but it is best to scald it in hot water before making it into a net, so as to insure a soft substance in which to catch the fragile creatures without injuring their wings or plumage. The net should be made round at the bottom, and be about a yard in length. Purchase a yard of mosquito-netting; it is sold two yards in width, and the quantity which is not used for the net serves to cover the breeding-cages, which are about to be described.

Another essential is a breeding-cage for caterpillars, and, as several are required if many butterflies and moths are to be reared, the following plan is a good one to adopt. Procure a small wooden box, about 6 or 8 inches long, or even larger, and about 3 inches deep; empty chocolate boxes are serviceable for the purpose. In each corner fix upright, with a couple of tacks, a piece of cane about 8 or 10 inches in length. Over this stretch a piece of mosquito-netting, tacking it to the edge of the box all round, except at one side, where it should be left loose, so as to be fastened down at will with two or three stout pins. The loose side can then be raised to give the caterpillars fresh food, and to remove dirt or refuse. Breeding-cages that one can purchase at any naturalists’ outfitters are made very handily of wood, zinc, and glass, and of course are very durable, but those described above last well for a season, and have the merit of being of no expense.

To procure good moths and butterflies with bright and uninjured plumage, it is best to rear them from the caterpillar stage of development, but as all varieties are not easily found, the net is usually the collector’s first resource. Raising caterpillars from the egg is a very interesting process, but it is rather tedious, and requires more knowledge and experience to meet with success than finding the insects in the next stage of development, and keeping them till they reach the perfect state.

When starting for a day’s ramble butterfly-hunting, one of the great charms seems to be the delightful uncertainty about the sport which may fall to one’s lot, so it is as well to provide for all contingencies, taking the net, poison-box, or bottle, a tin for caterpillars (which should be perforated at the top), a nest of glass-topped pill-boxes for specimens of any butterfly or moth one may wish to take home alive, and envelopes for butterflies when killed in the net. The latter may be made of note-paper, by cutting a long square of paper and folding it in a triangular shape, and then turning up the edges of two sides, so as to make a little bag.

Butterflies travel well placed flat in these envelopes, and should be set directly home is reached. A small cork collecting-box is also useful, together with some insect-pins, in case one gets many specimens, some of which can be pinned into the box preparatory to setting them on the return home.

Insect life is so prolific in Teneriffe, and one sees so many strange and curious animals, that anyone really interested in Entomology is certain to find specimens to bring home, such as the “Praying Mantis,” found frequently on half dead thistles in “barrancos” and on shrubs, the many varieties of large grasshopper, and the gorgeous coloured dragon-flies flitting about and killing butterflies in a rather wholesale manner.

All these insects are of such interest, that it is as well to be provided with various appliances for carrying them on the homeward journey.

As sunshine and brightness prevail in Teneriffe during the winter months, it is not necessary to choose a “likely” day, as in England, in order to have a good day’s sport, indeed there seem to be more butterflies on the wing on the days that are not too brilliant. On the very sunshiny days the butterflies are about in the greatest quantities in the early morning, retiring at noon to more shady or sheltered spots. A nice quiet sheltered little dell, covered with rough herbage and cactus by the sides of the barrancos, is a very favourite spot. The barrancos are dry river-beds, sometimes of great extent, with large boulders and rocks thrown about in wild confusion; generally speaking they are intersected by a path, up which one can ride or walk, leading up the mountains to different villages and hamlets.

Occasionally, during the winter months, a great quantity of water runs down the barrancos, but the supply only lasts a short time, soon drying up, and leaving a few small stagnant pools here and there, and these in turn soon disappear.

Walking over much ground is hard work, as the country is steep, and rough with stones and rocks. I advocate strongly the use of mules, as being the most pleasant mode of locomotion. They are so sure-footed and easy in their quick walk, that one feels far less tired after a long day’s excursion on mule-back up the mountains and barrancos, than by any other mode of locomotion. The muleteer carries all necessaries, together with luncheon, and one is able to stop and alight where fancy dictates or butterflies abound. Mules can be hired at Villa Orotava, the charge being one dollar, or five pesetas, for a short day; beyond this a small gratuity to the muleteer makes him pleased and happy.

There are many completely uncultivated spots up the mountains, intersected by little bye-paths along which the mules can walk; these are perfect “Eldorados” for moths and butterflies, and one must be busy with net and poison-box, not forgetting the tin case in which to place larvæ for the breeding-cage, and especially remembering to carry home some of the plant upon which they feed.

Some of these places are so rough and thick with bramble growth, and vegetation of like nature, that walking is really hard work. The lava-rocks are sharp, and the numerous grasses with hooks, such as the “Amour Sec,” together with the thorns of the prickly pear, make a formidable barrier for the pedestrian. There are, however, no poisonous snakes to dread, no biting animals of any sort larger than flies, so that the inconvenience of the thorns and pricks is all that need be feared.

On returning home from the expedition, all the various wants and requirements of the specimens must be attended to. The caterpillars have to be put into breeding-cages, which should have been already prepared for them. Different kinds which feed on the same plant may be put together. Care must, however, be taken not to put any cannibal species, such as the Armigera, among the others; also moth and butterfly larvæ should be kept separate.

For moth larvæ it is essential to have some fine earth (previously baked to destroy the ants, which are very troublesome) spread on the bottom of the box, from 1 to 2 inches thick. The caterpillars bury themselves in this when they have finished feeding, making for themselves a slight mould of earth, welded together with silk-like threads. Different species, however, vary in their mode of procedure, some making very slight, and others more pronounced cocoons; while yet others make quite an oval shell, choosing only the finest grains of earth with which to construct their houses.

It is said that some sort of dried leaf answers the purpose of earth, and is less likely to injure the moth’s plumage, but the former mode has been found to be perfectly successful. Place the plant on which the animal is to feed in a moist pot of earth, or in a bottle of water, so as to keep it fresh. If the latter mode is adopted, care must be taken that the animal does not drop into the water; so it is best to choose a wide-mouthed bottle, putting a bung with a hole in it as a stopper, and inserting the plant through the hole into the water. The earth should be kept slightly moist, and many people give caterpillars a gentle spray of water occasionally to take the place of dew, which they would have in their natural state. It is a good plan to let them have a little of the early morning sun upon them, as it serves to keep them in health, but they cannot bear the sun of mid-day.

For butterfly larvæ the same procedure is required, except that only a thin sprinkling of earth is wanted at the bottom of the box for the purposes of cleanliness.

When the larva of the butterfly is about to develop to its pupa state, it readily crawls up the box and netting, suspending itself, from the top head-downwards, and the netting serves as a good foot-hold for the butterfly when it appears. If possible the chrysalides should remain as they place themselves until the next stage of development is reached; because, unless they are able to expand their wings while in this position, deformity is likely to ensue.

The majority of butterfly chrysalides are naked, and of an angular form, some being remarkable for the brilliancy with which they are spotted with gold and silver.

The Vanessa family is an example of this, the Vulcania and Huntera being especially brilliant.

Caterpillars of the “Skipper” family make a web-like covering of silk for the reception of the chrysalides, but there has been hitherto only one species of this family found in Teneriffe.

Many caterpillars of various kinds kept during the winter months were very subject to the raids of the Ichneumon fly. This fly lays its egg on the larva, and it is not easily perceived on the animal unless looked for through a magnifying-glass.

The caterpillar lives on, and seemingly thrives, but after it has turned to its pupa state the fly develops, and a fine Ichneumon fly appears in the breeding-cage instead of the expected butterfly. There are large and small varieties of this fly, the former laying only one or two eggs on the caterpillar, the latter a great many, and they emerge from the chrysalis in corresponding numbers.[1] The only remedy seems to be to inspect all larvæ through a magnifying-glass, and to reject any infected specimens. Pieris Cheiranthi is particularly liable to this fly. The red fungus found on the Tithymali moth caterpillar is another disease, but is not very common.

[1]This occurrence is mentioned by Gilbert White in his “Natural History of Selborne,” v. “Observations on Insects and Vermes,” p. 519. Ed. 1813.

Caterpillars should be handled as little as possible while removing them to their fresh food. As a rule, they crawl on to the fresh supply at once, but in the case of very small specimens a camel-hair brush should be used to lift them from one place to another. Many of them emit a fluid when touched. The Tithymali spits out a quantity of green fluid when disturbed.

Butterflies generally seem to be found in the greatest numbers in the barrancos early in the year. When, however, the fields get green and vegetation increases, they desert the barrancos and take more to the fields and country, with the exception of the Argynnis Lathonia, a variety which more particularly frequents barrancos.

The time of appearance of all species takes place from two to four weeks later the higher they are up the mountains. The south part of the island is not so fertile a place for Lepidoptera as the north; perhaps this is owing to the more sparse vegetation on that side.

Many species are found inland, while some are peculiar to the coast. The heights and localites in which all the different kinds are found have been indicated as far as possible in the description of the various species.