454 PROCEEDINGS OF THE NATIONAL MVSEUM. vol. xxix. 



which he says paid no further attention to the father, with large gill 

 openings, with perfectly transparent bodies, and, strangest of all, 

 with both pectorals and caudals, which they used freely. This caudal 

 was a continuous tin-fold, extending from a point anterior to the true 

 dorsal backward around the tail and forward on the ventral surface to 

 the anus; that is, it was a structure identical in appearance and use 

 with the permanent caudal of the eel. This fin-fold is permanent in 

 the Falkland Island genus, Protocampm^ which Giinther thinks may 

 be an embryonic Nerophien. YarroU rt^ports such a temporary tin- 

 fold in salmon embryos. 



In 1840, Krohn, from dissections made the year previous, affirmed 

 that the female 11/ ppocamjnis hrevirostris bears the egg-pouch, and 

 that this has lining it a '■'' schleimhaut gefasKreichen^''' thus conlirming 

 Rathke. In this same year, this later writer described a female S. 

 sequoreus (a Nerophien) with eggs on the belly, and says that the 

 ovary (testis?) of this specimen contained ova of various sizes, each 

 with a germinal vesicle. Sections of the testis of S. ftoridse, show 

 large vesicular spermatocytes lining its lumen. Probably these are 

 what Rathke saw. 



Von Siebold, desirous of settling this much-controverted question, 

 spent some time at Trieste in 1811, and in the following year published 

 his results. He found that the niales of Syngnatlms ri/nchmius, pela- 

 gicus^ typhle, and acus, and of Hippocampus longirostris and hreviros- 

 tris^ bear the eggs. He got these results: (1) by "stripping" the 

 tishes and noticing the white fluid containing spermatocytes; (2) by 

 dissecting ovaries and testes and noticing the golden-red eggs shining 

 through the ovarian walls; (3) by making microscopic examinations 

 of the products of 1 and 2. He wondered how Rathke or anyone 

 else could have fallen into such palpable errors. 



The French naturalist, Quatrefages, pul)lished in this same year 

 (1842) a paper on the embryos of S. ophidian in which he described 

 the external structures of .young nearly ready to hatch. These eggs 

 are plastered on the belly in the (at this time) much thickened integu- 

 ment of which they make depressions. The shells are filled with an 

 albuminous fluid in which the young move. 



Kro3^er, whose book is dated 1853, says that the females of S. typhle 

 are usuall}^ larger than the males, and that their numbers are about ten 

 times as great. He finds that the eggs are arranged in regular rows 

 in the pouch, embedded in mucus, and that this mucus disappears and 

 the lids of the pouch sink in, but are not absorbed after gestation. 

 He conjectures that fertilization takes place at time of transfer. 



Vogt and Pappenheim in 1859 say that when the young leave the 

 pouch the yolk sac is completely absorbed, which is not true of the 

 Siphostomas at Beaufort. They examined fishes by hundreds and 

 never found a female with or a male without a pouch, which they 



