40 PROF. F. J. BELL ON ECHINANTHUS TUMIDUS. [Jan. 15, 



Considering that these fishes have shown no tendency to mon- 

 strosities, have been well formed, and grown fairly in proportion to 

 the young of the true American Chart hatched at the same time, I 

 cannot res^ist thinking that it may be possible that these two fish, 

 although so widely differing in colour, may be merely varieties of 

 one species, descendants from one common stock. This question, 

 however, will be more appropriately discussed when we possess fish 

 a year or two older. 



"On November 29th, 1883, about 4500 eggs were obtained from a 

 Lochleven trout which had been hatched in 1875, and these were 

 milted from a young Salmon, such as I have already described, which 

 was taken for this purpose from pond C. 130. These eggs were 

 deposited in box 88. 



About 3000 eggs were taken from a Lochleven Trout of the season 

 of 1875, and fertilized from the milt of two American Charr. These 

 eggs were deposited in box 92. 



About 2695 eggs were taken from an American Charr and milted 

 from a young Salmon from pond C. 130. These ova were deposited 

 in box 96. 



About 1000 eggs were obtained from a Brook-Trout of about ilb. 

 weight and fertihzed from the milt of the dead young salmon already 

 referred to. These eggs were deposited in box 100. 



5. On the Generic Position and Relations of Echinanthus 



twnidus, Woods; By F. Jeffrey Bell , M.A., Sec. 



R.M.S., Professor of Comparative Anatomy in King's 



College. 



[Received December 18, 188.3.] 



(Plates II. & III.) 



For some years past our knowledge of the Echinoidea has been 

 increased by the descriptions of various new species, published by the 

 Rev. J. E. T. Woods, which have appeared in the ' Proceedings ' of 

 that excellent body the Linnean Society of New South Wales. 



Of such forms the most remarkable was that which was distin- 

 guished by him as Echinanthus tumidus^ ; my knowledge of thisspecies 

 was confined to the short description which he gives of it, but that 

 description was sufficient to rouse my curiosity. It was, therefore, 

 with the greatest pleasure that I found an example of it among a set 

 of specimens which Mr. E. P. Eamsay lately submitted to me for 

 determination. The original diagnosis had made it clear to my mind 

 that the species did not belong to the genus Echinanthus ; and an 

 investigation of the characters of the specimen itself lead me to the 

 belief that it presents very important points of difference from any 

 form yet described. 



1 Proc. Linn. Soc. N. S. W. ii. p. 169. 



