[13] Müller considers a nerve rising jointly with the Vagus in Petromyzon to be this nerve (Fig. 45, hy).
[14] On the development and structure of the dentition of Scarina, see Boas, “Die Zähne der Scaroiden,” in Zeitschr. f. Wiss. Zoolog. xxxii. (1878).
[15] This applies to individuals only growing up under normal conditions. Dr. H. A. Meyer has made observations on young Herrings. Individuals living in the sea had attained at the end of the third month a length of 45 to 50 millimetres, whilst those reared from artificially-impregnated ova were only from 30 to 35 millimetres long. When the latter had been supplied with more abundant food, they grew proportionally more rapidly in the following months, so that at the end of the fifth month they had reached the same length as their brethren in the sea, viz. a length of 65 to 70 millimetres.
[16] Ray Lankester considers it to be a portion of the long denticulated cornua of a genus Eukeraspis allied to Cephalaspis.
[17] Ekström, Fische in den Scheeren von Mörkö.
[18] Will probably be found.
[19] We distinguish these sub-regions, because their distinction is justified by other classes of animals; as regards freshwater fishes their distinctness is even less than that between Europe and Northern Asia.
[20] Martens (Preuss. Exped. Ostas. Zool. i. p. 356), has already drawn attention that a Barbel, said to have been obtained by Ida Pfeiffer in Amboyna (Günth. Fish. vii. p. 123), cannot have come from that locality.
[21] In the following and succeeding lists, those forms which are peculiar to and exclusively characteristic of, the region, are printed in italics; the other regions, in which the non-peculiar forms occur, are mentioned within brackets [].
[22] Lates calcarifer in India as well as Australia.