74 Rey. T. R. R. Stebbing on the Genus Bathyporeia. 
X.—On the Genus Bathyporeia. 
By the Rev. THomas R. R. Sreppina, M.A. 
[Plate III.] 
To Lindstrém’s original species, Bathyporeia pilosa, two 
other species, Robertsont and pelagica, have been added by 
Mr. Spence Bate. Of the last, however, he had seen but a 
single imperfect specimen, and none but dead imperfect speci- 
mens of the other two. As I have been more fortunate, and 
have been able to examine perfect and living specimens of 
these beautiful little creatures, I have no hesitation in re- 
ducing all three forms to a single species, the original Bathy- 
poreia pilosa. There can scarcely be a doubt that what has 
been figured as B. pilosa is the female, that B. pelagica is its 
male, and that B. Lobertsoni is also the male not yet arrived 
at maturity. 
I have taken all three forms on, or rather in, the sands 
at Llanfairfechan. One specimen of the male I took at low 
tide near Bangor, one of the female at Pwllheli; so that the 
species is probably to be found all round the coast of North 
Wales. It burrows in the sand to the depth of half an inch 
or a little more, and exhibits very great activity in this pro- 
ceeding. When in water it is equally vivacious, darting about 
in all directions. 
The eyes are faceted, red, and in the mature animal large 
and kidney-shaped, but small and round in the young. The 
eyes increase by addition to the number of facets—a mode of 
growth well known in regard to these organs in the Amphi- 
poda, and only requiring notice here because the eyes are 
given as round in the figure and description of Bathyporeta 
Robertsont. 
The upper antenne do not supply, as was supposed, a mark 
of distinction between the form given as L. pelagica and the 
other two, since in all alike the secondary appendage to the 
flagellum has one large articulus followed by a very slender 
small one. They are also alike in other respects, and notably 
in the shape of the large first joint, which stands boldly out 
in a line with the head, but forms a considerable angle with 
the two following joints, very diminutive by comparison, and 
attached to an excavation some little way from its compressed 
distal extremity. 
The lower antenne do undoubtedly differ in the three forms ; 
and it is upon these organs that most stress has been laid in 
distinguishing the supposed species. The principal difference, 
however, is in the length of the flagellum, which is very short 
