405 Part I1I—LHighteenth Annual Report 
collection at Bay of Nigg. It measures about 20mm. from the extremity 
of the rostrum to the base of the dorsal shield. 
Jaxea nocturna, Nardo. 
In my paper on Clyde tow-net and other gatherings published in 
Part III. of the Seventeenth Annual Report (1899) I reported the 
occurrence of an interesting lucifer-like crustacean in the Firth of Clyde. 
I stated further that this crustacean had been identified with a form, also 
from the Clyde, which had been described in the Proceedings of the Royal 
Society, Edinburgh, vol. xv., p. 420, figs. 1 and 2 in the text (1889), by 
the late George Brook under the name of Z’rachelifer. In some additional 
remarks which immediately follow what had been stated in regard to 
Brook’s description of Trachelifer, it is clearly shown that this 
“ Trachelifer” was really the young of Calliaxis adriatica, Heller. 
Nothing further transpired concerning these Clyde organisms till last 
summer, when I received from Mr. F. G. Pearcey, the naturalist on board 
the ‘‘ Garland,” a number of fragments of a small Vephrops-like crustacean 
which he had found in the stomachs of some gurnards captured in the 
vicinity of Ailsa Craig, near the mouth of the Clyde estuary. It was at 
once evident that these fragments did not belong to Nephrops norvegicus, 
though in some respects they had a more or less close resemblance to that 
crustacean. ‘The species, however, could not be made out for a consider- 
able time. At first it was thought that the fragments might represent 
one or other of the described species of Wephropsis, but with none of 
these would they fit in satisfactorily. Failing, for various reasons, to 
arrive at a satisfactory solution of the difficulty, I applied to the Rev. T. 
R. R. Stebbing, who has not unfrequently proved in such matters to 
be a ‘friend indeed;” and he, after some investigation, found that 
the fragments which had given us so much trouble belonged to a species 
which Nardo in 1847 had described under the name of Jaxea nocturna. 
He, moreover, pointed out (as he does also in his History of Crustacea, 
p. 187) that Jaxea nocturna is identical with Calliaxis adriatica, Heller, 
described in 1856 ; and as T’rachelifer is the young of Calliazis, so also, 
as a matter of course, is it the young of Javea. The position of the 
species may therefore be stated thus :— 7 
Jaxea nocturna, Nardo (1847). 
— 1856. Calliaxis adriatica, Heller. 
= 1889. Trachelifer, sp. (jun.), Brook. 
Another point of interest that may now be considered is the habitat of 
Jaxea. Can we claim it as a member of the Clyde fauna? In regard to 
this point I am inclined, after a careful consideration of all the circum- 
stances, to consider that we may fairly make this claim. We find these 
juvenile forms occurring at more or less frequent intervals in various 
parts of the Clyde area,* and occasionally in considerable numbers, two or 
three different stages of development being represented, and latterly, as 
pointed out, fragments of several adult specimens have been found in the 
stomachs of gurnards caught in the vicinity of Ailsa Craig. From the 
state cf preservation in which these fragments were found it is scarcely 
likely that the time that had elapsed between the capture by the gurnards 
of the specimens to which the fragments belorged and the capture of the 
curnards themselves in the “‘Garland’s” trawl-net could have been very 
great. All this seems to indicate that the adult Jaxea are not very far 
off from the places where these larvee and fragments were obtained. It 
* Trachelifer was obtained in a bottom tow-net gathering collected at Station V. 
ee Bay)—a station well within the limits of the Clyde estuary—on October 11th, 
1899, 
