114 MR J. T. CUNNINGHAM ON THE 



Order II. ANACANTHINI. 

 Fam. 1. LYCODiDiE. 



I am not aware that the development of any species of this family has been 

 studied. 



Fam. 2. GADiDiE. 



Gad us. — A large number of the species of this genus have been studied— 

 Gadus morrhua, merlangus, and wglefinus by myself, G. morrhua by John A. 

 Ryder. The eggs are, of course, closely similar except in size. The largest of 

 the three species above mentioned are those of G. ceglefinus. The eggs are 

 pelagic, the yolk is optically homogeneous, and destitute of oil globules. In the 

 newly hatched larva the anus is not open, the rectum is in immediate proximity 

 to the yolk sac, the notochord is multicolumnar, the pelvic fins not developed, 

 and the mouth not open. In the neAvly-hatched haddock the eyes are 

 considerably pigmented ; there are stellate chromatophores scattered over the 

 sides of the trunk, and a single row of them along the ventral edge of each 

 side of the tail. 



Motella. — The development of Motella mustela, Linn., the five-bearded 

 rockling, has been studied by George Brook {Jour. Linn. Soc, 1884, vol. xviii.). 

 The eggs were deposited in his aquarium, under observation. The eggs are 

 pelagic, and have usually one large oil globule, exceptionally more than one. 

 (The buoyancy of the egg is in the paper attributed to the oil globule, an error 

 which has been repeatedly made ; there are many pelagic ova which have no oil 

 globule.) The eggs are somewhat oval in shape and slightly variable in size. 

 Length of longer axis, -655 to 731 mm.; of shorter, -040 to 716 mm. Hatching 

 took place in 5^ to days, at a temperature of 51° to 62° F. In the newly 

 hatched larva the rectum is immediately behind yolk, but not open, and not 

 extending to the edge of the fin-fold. The eyes are slightly pigmented, and 

 there are two small patches of pigment on the tail. The anus was not open 

 seven days after hatching ; the mouth not open at hatching. Spawning took 

 place in May and June. 



Motella argentea, Rhein. — The young in various stages were identified and 

 described by A. Agassiz, July 1882, in Young Stages, pt. iii. (Proc. Amer. 

 Acad. Arts and Sci., vol. xvii.). In the youngest stage, 4 mm. in length, the 

 embryonic fin-fold is continuous, notochord multicolumnar (a point not ascer- 

 tainable from Brook's figures), pelvic fins palmate and large. In oldest stage, 

 3*4 cm. in length, two dorsal and one anal fin all distinct; pelvic fins very long 

 and narrow. There is some uncertainty about the identity of the specimens; 

 they may belong not to Motella argentea, but to some species of Onus. 



