LARVAL AND POST-LARVAL FISHES—REGAN. 133 
Chionedraco kathleenae, Regan (P1. IV, figs. 2, 3). 
A larva of 21 mm. was taken by the “Terra Nova” off Cape Evans at a depth 
of 10 metres on October 19th, 1911. This is not quite so advanced as the young 
Pagetopsis of 19-20 mm. From these it is readily distinguished by the longer tail 
and the more numerous myotomes (about 60), whilst the pelvic fins are scarcely 
pigmented except between the spine and the first soft ray. A fish of 32 mm. from the 
“ Discovery ” collection is much more advanced, but the dorsal and anal rays are still 
undeveloped. 
Cryodraco (Pl. IV, fig. 1). 
Three specimens, 16, 17 and 21 mm. in total length, from Ross Island 
(“ Discovery ” collection) may belong to an undescribed species of this genus. The 
myotomes number 55 or 56, fewer than in C. atkinsoni, in which I count 62. The 
body is crossed by two dark bands, the anterior on myotomes 27 to 29, the posterior 
on myotomes 40 to 42; there are indications of a third band at the base of the caudal 
fin. The slender form, produced snout and elongate pelvic fins further distinguish 
these fishes from larval or post-larval Pagetopsis and Chionodraco. 
The data given above with regard to the breeding and development of the 
Nototheniformes may be summarized as follows :— 
Of the Bovichthyidae nothing is known, and examination of the material in the 
Natural History Museum gives no results. 
The breeding season varies considerably ; approximate dates are May and 
September for species of Notothenia, July for Trematomus hansoni and T. bernacchii, 
November for Pleuragramma antarcticum, January and May for species of Artedidraco, 
May for Champsocephalus gunnari, etc., ete. 
The eggs vary in diameter from 1 to 4 mm. when taken from ripe females 
preserved in spirit ; the diameter would no doubt be greater if eggs freshly taken from 
the sea were examined. The Nototheniinae seem to have the smallest eggs, 
Artedidraco and the Chaenichthyidae the largest. In all probability the eggs are 
demersal throughout the group, and in some species of Notothenia they are known to 
adhere together in masses. 
In some of the Notothenimae the newly hatched larvae are about 6 mm. long, 
but in Artedidraco and the Chaenichthyidae they are probably twice as long or 
even more. 
The newly hatched larvae have a distinct mouth, the membranous median fin 
_ extends forward above to the head and below to the yolk-sac; the anus is situated at 
or a little behind the posterior end of the yolk-sac, and at the edge of the fin- 
membrane ; pectoral fins are present, but the pelvics do not appear until much later, 
except in the Chaenichthyidae. During growth the caudal is formed and assumes its 
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