250 BULLETIN OF THE UNITED STATES FISH COMMISSION. 



arch is more distinctly curved. Variations, however, are frequent in the larger exam- 

 ples. The caudal rays proceed from a nearly vertical line in the smaller specimen, 

 but from a semicircle (/. e., a line convex backward) in the larger. The opercular 

 region also differs, but the action of the gastric juice had made changes in the small 

 specimen. The thickness and narrowness of the body are more or less diagnostic at 

 this stage. 



ON THE EGGS AND LARVAE OF THE TORSK (BROSMIUS BROSME). 



The literature on the spawning and development of the torsk is very meager. 

 Thus, Couch says it comes from deep water near the coast at the time of spawning, 

 which is in January and February. Parnell, again, states that it spawns in April and 

 May amongst the seaweeds along the coast. Day, like Parnell, seems to have copied 

 this remark without query. Brook, in the Report (1886) of the Fishery Board for 

 Scotland gives, on the authority of the fishery officers, March at Wick, May and 

 June at Peterhead, and the same two months at Berwick. Dr. Fulton, who examined 

 two very fine specimens of 34 inches, and weighing, respectively, 15 pounds 5£ ounces 

 and 15 pounds, calculated that the partially developed ova in the former were about 

 2,283,979 in number, whereas in the latter, which, he thinks, had discharged part of 

 them, the ovaries contained 790,064. In the latter example, 40 or 50 in 3,612 ova 

 which were counted were large clear eggs, having a diameter of 1-4 to 1-32 mm. 



Little was known of the breeding of the species, though from its relationship 

 with the ling and the rockling it was supposed to have an egg with an oil-globule. 

 Various attempts had been made by the Fishery Board for Scotland and others to 

 secure ripe examples, but without success. The energetic efforts of Dr. Fulton and 

 the fishery officers (among Avhom must specially be mentioned Mr. Mackie, assistant 

 officer at Peterhead, and Mr. Duthrie, assistant officer at Lerwick) at last solved the 

 difficulty. Mr. Mackie procured ovarian eggs, the latter a fine series of fertilized ova. 

 In the ovarian ova a number of unripe were mingled with others more or less ripe, 

 the diameter of the latter in a fluid consisting of one-half saturated solution of picric 

 acid and half spirit, ranging from 1*2573 to 1*3335 mm., the latter being approximately 

 the average of ripe eggs after preservation. The ripe fertilized eggs, the securing of 

 which under many difficulties reflected great credit on Mr. Duthrie, were got on the 

 25th of May. He had less trouble in obtaining females; it was the condition of the 

 males which puzzled him; for the spermaries are small, reaching in the proportions 

 only from 2 to 3 inches in a male of good size, and having the form of a small frilled 

 cord or ribband. They thus differ materially from the condition in the cod and its allies. 



The ova on their arrival from Shetland were almost dry, and their hardihood was, 

 perhaps, partly due to the fact, so often seen in other forms, that they had reached a 

 certain stage of development, viz, the fourth day. They had an average diameter of 

 1*3335 mm., so that the preserved examples from Peterhead must have been exception- 

 ally tine or had been slightly dilated. The large oil-globule, which had a diameter of 

 0*2286 to 0*2007 mm. appeared, under the lens, of a pale reddish-brown hue, but by 

 transmitted light of a pale red; indeed, no pelagic egg, with the exception of the 

 sand-eel, has presented a more distinctive color. In some a series of minute fatty 

 granules were also present under the large globules. The zona radiata is remarkably 

 tough and resistant, and the egg can only be ruptured by the exercise of considerable 

 force. A series of boldly marked punctures are present and they have in some views 



