found in Dublin Bay and its vicinity. 



133 



Ophiura texturata. Solaster endeca. 



O.albida. S.papposa. 



Ophiocoma filiformis, a single spe- Asterias aurantiaca. 



cimen. Spatangus -purpureas. 



0. rosula. Echinus sphara. 



I raster rubens. Amphidotus. cordatus. 



1. . violacea. Echinocyamus pusillus. 

 Cribella oculata. 



MOLLUSCA. 



Doris tuberculata, not common. 



D. bilameilata, Johnston. Syn. D. verrucosa, Fleming's Brit. Anim. 



The peculiar arrangement of the branchiae of this species is over- 

 looked by Dr. Johnston, the specimens from which his description 

 of the species was derived having been preserved in spirit. As I 

 had an opportunity of comparing several living specimens together, 

 it may be as well perhaps to subjoin a description of its outward 

 characters. 



Length one inch and three-fourths ; body ovate, the larger end 

 anteriorly depressed ; cloak tuberculated, mottled with deep brown ; 

 tubercles rounded, white, elevated, and not all of an equal size ; a 

 broad band of brown, ^ of an inch in width, passes along its centre, 

 commencing at the dorsal tentacula and terminating at the branchiae ; 

 the tentacula also are encircled by a brown shading. Branchiae 

 conical, pinnate, varying from twenty-four to thirty in number, ar- 

 ranged in the form of a crescent or like the capital letter C, the horns 

 of the crescent being much incurved ; the convexity is anterior ; 

 the branchiae are longest in the centre of the crescent and diminish 

 greatly towards either side. A short process is frequently seen be- 

 tween many of the branchiae, having somewhat the appearance of 

 the remains of a branchia which had been broken off ; tubercles also 

 cover the space enclosed by the branchial apparatus : dorsal tenta- 

 cula thick at the base, conical, and without a sheath surrounding 

 them. Number of branchiae in young specimens as many as in ma- 

 ture ones. 



It deposits its ova in ribbon-like gelatinous masses early in the 

 month of March. 



Found in great abundance at Williamstown above low- water mark. 

 Doris pilosa, not at all common. 



Several varieties of a Doris occur at the same locality as Doris 

 verrucosa, which I was at first inclined to regard as a variety of Doris 

 pilosa, but which I now am inclined to consider as distinct from 

 that species, from which it differs in several particulars ; in having 

 the dorsal tentacula surrounded by a notched sheath ; in size, the 

 largest specimens attaining the length of one inch and three-eighths ; 

 and in colour, which is various. One variety of this elegant Doris is 

 of a soot-like black colour, and this is evidently the Doris nigricans 

 of Fleming. A second principal variety is of a delicate and lively 

 canary colour. All the other varieties present different shades of 

 these two colours, or are colourless or pure white ; this last variety 

 is frequently met with. 



