The Ternate group shows decidedly closer relations with New Guinea than the Amboyna group. Thus, among the Helices, the markedly Papuan genus Papuina is represented by 7 species in the Ternate group, but by 1 in the Amboyna group. Again, the Cristigibba section of Planispira, which is a Papuan form, has 4 representatives in the northern group, but only 1 in the southern. Certain points of connexion with Celebes come out in the southern group which are wanting in the northern; thus of Chloritis there are 8 species in Amboyna, 0 in Ternate, 3 in Celebes.

In the Moluccas the Helicidae, for the first time as we move eastward from India, gain the ascendancy over the Naninidae, the numbers being, Helix 55, Nanina 36. If we take the groups separately, we find that in the Amboyna group the proportion is 22 to 23, while in the Ternate group it is 33 to 13, an additional proof that the Amboyna group is far less Papuan than the Ternate. Of Planispira, the most characteristic sub-genus of Helix, there are 12 species in the Ternate group, and 5 in the Amboyna. The section Phania, which contains 4 species of the finest Helices known, is quite peculiar to the Ternate group. One species of Obbina, a sub-genus markedly Philippine, occurs in each group. Several of the Indo-Malay land operculates (e.g. Ditropis) reach their limit here, and here too we have the last Clausilia (strangely absent from the Amboyna group). Amphidromus is not reported on sufficient authority to warrant its insertion in the list.

Land Mollusca of the Moluccas. (T = Ternate, A = Amboyna[370] group)

Helicarion1 A
Euplecta1 A
Xesta6 A, 4 T
Macrochlamys1 A
Lamprocystis4 A, 2 T
Macrocycloides4 A
Sitala1 A
Kaliella3 A, 1 T
Trochomorpha3 A, 3 T
Endodonta1 A
Patula1 A
Plectotropis1 T
Eulota1 A
Chloritis8 A
Planispira5 A, 12 T
Cristigibba1 A, 4 T
Obbina1 A, 1 T
Phania4 T
Albersia3 T
Camaena1 T
Papuina1 A, 7 T
Pupa3 A
Vertigo2 A
Clausilia1 T
Opeas4 A, 4 T
Subulina1 A
Tornatellina1 A
Vaginula1 A
Melania18 A, 4 T
Faunus1 A
Vivipara1 A
Acmella1 A
Diplommatina4 A, 2 T
Registoma1 T
Pupinella1 A
Callia2 A
Leptopoma4 A, 5 T
Lagochilus1 A, 1 T
Ditropis3 A
Cyclotus4 A, 6 T
Omphalotropis3 A
Georissa1 T
Helicina6 A, 3 T

(d) The Philippine Province.—In the extraordinarily rich development of their Mollusca, the Philippines form a remarkable contrast with the poverty of the adjacent Malay islands. No less than 727 species of land Mollusca alone are known from the group, amongst which are included some of the finest and handsomest forms yet discovered. The main features of the fauna are Indo-Malay, with the addition of a certain Australasian element, and a remarkable development of individual characteristics.

The principal indigenous feature is the profuse abundance of the genus Cochlostyla, a group of large and elegant land shells, partly helicoid, partly bulimoid in shape, many of the species of which are covered with a curious hydrophanous epidermis. They are in the main of arboreal habits, living in the tops of the enormous forests which cover the greater part of the islands. As many as 247 species, belonging to 15 sub-genera, have been described.

Fig. 210.—Cochlostyla (Chrysalis) mindoroensis Brod., Mindoro, Philippines.

Fig. 211.—Cochlostyla (Orthostylus) Portei Reeve, Luzon. × ⅔.