81 



Other foeluses from a third fish were two and a quarter inches 

 in length, about one fourth the length of the parent. The 

 yelk-bag had disappeared, but the abdomen still presented a 

 fissure, or linear umbilicus, extending from between the pectoral 

 fins to near the anus, separating the ventral fins from each other. 

 These last foetuses had escaped from their ovarian sacs, and were 

 contained in the oviduct, which was very much enlarged. The 

 cornea had become divided as in the adult. 



It was obvious from comparison, that the older foetuses consisted 

 of a larger mass than that of the younger ones with the yelk-sac. 

 In other words, the fostuses had grown at the expense of other 

 materials than those contained in the yelk. This additional nou- 

 rishment could only be derived from the fluids secreted from the 

 vessels of the parent into the cavity of the embryo-sac, and their 

 subsequent absorption by the foetus. Such a mode of nutrition 

 exists in Torpedo, Embiotoca, and Blenny. 



Referring to some allusions in Prof. Wy man's paper, in rela- 

 tion to the mode of development of EmbiotGCoidce, Mr. Charles 

 Girard said he had recently examined several genera and species 

 of that remarkable group of fish, and, were his observations not 

 to appear soon in print,* he should feel more at liberty to enlarge 

 upon that subject. Within the body of the species to which he 

 gave the name of Embiotoca lineata, he found young, three 

 inches in total length and one inch in depth, exhibiting a struc- 

 ture of the dorsal and anal fins, similar to what is said to exist 

 in Rhacochilus toxotes ; f the posterior margin of the cau- 

 dal being truncated, whilst it is more or less crescent-shaped in 

 the adult. An elongated jet black spot was also observed towards 

 the base of the anterior portion of the soft part of the dorsal fin. 

 In Holconotus rhodoterus, as many as sixteen young were de- 

 tected, being about an inch or a little less in total length. The 

 vitelline abdominal sac was still present, leading to the inference 

 that they had but recently escaped from the egg-shell. Their 

 general form was slender and elongated ; the head being rounded 

 anteriorly and deeper than the body, and the snout much less 



* Proc. Acad. Nat. Sc. of Philad. Vol. VII. August, 1854. 

 t Amer. Journ. of Sc. Second Series. Vol. XVII. 1854, p. 387. 

 PROCEEDINGS B. S. N, H. — VOL. V. 6 DECEMBER, 1854, 



