Holt and Caldeewood — Beport on the Rarer Fishes. 891 



Colours. — The grey of the undersurface was well marked in all living' examples 

 which we have seen, and is not, as is frequently the case in R. batis, the effect of 

 post-mortem changes. 



Breeding. — We have never recognised the egg-purse of this species, nor does it 

 appear to have been described by other observers. 



Kidneys. — We have examined these organs in two females, measuring 

 respectively 36 and 22^ inches across the disk. In both examples they are 

 asymmetrical, especially in the posterior region. The subjoined figure shows 

 the condition in the larger fish, and in the smaller one the conformation is 

 very similar, though not exactly the same. Attention has been drawn by 

 Professor Howes (" Jour. Anat. and Phys." xiv., p. 341) to the frequency of 

 asymmetry in the kidneys of R. clavata. The author figures several examples 

 (PI. XVII.), which in no case very closely resemble those before us, and suggests 

 that the variation may represent the inception of a "condition to be sooner or 

 later seized upon, and handed down to future generations of thornbacks as an 

 inheritance of the past" {op. cit., p. 421). From the examination of only two 

 specimens it is impossible for us to say whether the character has become fixed in 

 R. oxyrhynchus, or whether we have merely happened to remark two abnormal 

 examples. 



Kidneys of E. oxijrhynclius. H.ilf natural size. 



Raia fuUonica, Linnaeus. The Shagreen Ray. (Deep-sea). 



Raia fullonica, .... Collett, " Norges Fiske," p. 217. 

 „ „ .... GiJNTHER, " Proc. R. S. E.," XV., p. 206. 



A specimen measuring 44 inches in length was taken at 154 fathoms, off 

 Achill Head, on the 20th April, 1891. Otliers occurred at various depths between 

 32 and 80 fathoms, while one was caught in Killybegs outer harbour at 14 to 

 16 fathoms. 



The species is known to occur at depths ranging from 80 to 250 fathoms on 

 the coast of Norway (Collett), and Giinther has recorded an example from 

 100 fathoms in Loch Fyne. 



