448 Holt — On the Eggs and Larvce of Teleosteans. 



is somewhat remarkable, as the attachment process in the egg of Gobius* takes the 

 carmine stain very deeply and readily. 



The yolk (?/.) is colourless and translucent, and very finely granular. The 

 oil-globule (o. g.) appears to occupy a variable position, as in some other demersal 

 ova ; the embryos in different ova at the same time present such differences in 

 development as to induce the belief that the parent deposits them in batches from 

 time to time. Judging from Mr. W. Anderson Smith's account (Notes on the 

 Sucker Fishes, Liparis and Lepadogaster : Proc. Roy. Phys. Soc, Edin., vol. ix., 

 1886, pt. i., p. 145) the eggs of L. decandolii are all deposited at the same time, as is 

 the case with most demersal ova. In some of the ova before us the embryo at the 

 time of capture liad a long, free, caudal growth, others had no free caudal growth, 

 and only four protovertebra; (fig. 3), whilst intermediate stages occur. In the 

 least advanced stages a large Kupffer's vesicle (/". v.) was j^i'esent. The embryo 

 occupies a horizontal position in the egg, the yolk (y.) being laterally compressed. 

 Mr. Anderson Smith notices great irregularity in position in the embryo in the 

 eggs of Lepadogaster, but in my specimens the horizontal position appeared 

 constant. I did not experience the difficulty met with by that observer in 

 isolating the ova of this species ; on the contrary these appeared much easier to 

 isolate than such demersal ova as those of Ccutronotus, which adhere to each other, 

 and possess no attachment processes. 



The larva, on emerging (figs. 6 and 7), has a total length of 2'97 mm.,t of 

 which the pre-anal region occupies 2*08 mm. The yolk {y. and fig. 5) is small, 

 transversely elongated, and somewhat bilobed. Anderson Smith noticed that it is 

 smaller than in L. decandolii. The head is large, and the parts of the brain are easily 

 made out, the medulla {in. o.) rising to a conspicuous hump behind the cerebellum. 

 The eye is large, with a comparatively large pupil. The otocysts are large and 

 near the eyes. The top of the head and back are very much flattened, a condition 

 well shown in a dorsal view of the larva (fig. 7). The pectorals (7?./.) are stout 

 and fan-shajDed. The gut, which extends far back, is very large ; the anus (a.) is 

 perforate. The mouth {m.) is subterniinal, and the turning ujj of the mandibular 

 symphysis below, and short of, the anterior extremity of the upper jaw imjDarts a 

 characteristic appearance to the head. The marginal fins are narrow ; the embry- 

 onic caudal somewhat lanceolate, and a very narrow pre-anal fin (;:>. a.f.) extends 

 from the yolk to the anus. The only pigment I could detect is black, and takes 

 the form of small round chromatophores. These occur on the lower jaw, along 

 the ventral region of the yolk sac on the pectoral fin, dorsally and ventrally on 

 the gut, and in four ill-defined rows along the sides of the body, except at the 



* Cf. " On the Ova of Gobius "—Ann. and Mag. Nat. Hist., July, 1890, p. 37. 

 j- Some as long as 3-15 mm., and advanced in pigmentation. 



