Dr. Johnston on British Annelides. 9 



? . eyes none ; proboscis emaxillary : feet very numerous, 



all alike, uniramous, and all furnished with an inferior cirrus. 



1. Spinther oniscoides. Plate II. fig. 7. 



" Dredged off Castle Chichester (Belfast Bay) Aug. 26, 1844, in 

 6 — 10 fathoms, Mr. Hyndman," W. Thompson. 



Desc. Body ovate, convex dorsally, flat on the ventral surface, 

 of a uniform cream-yellow colour, rounded and obtuse at both 

 extremities, which are so much alike, that, without a close exami- 

 nation, the anterior is not to be distinguished from the posterior. 

 There is no head, tentacula nor tentacular cirri. With a com- 

 mon magnifier we perceive that the back is crossed by numerous 

 (about thirty) narrow roughish edges (fig. 8), the roughness 

 being produced by a series of minute bristles which scarcely pro- 

 trude beyond the skin : the ridges are regular and equidistant, 

 and are continuous with the feet on each side. The feet form a 

 close-set range round the body, interrupted only in front by a very 

 narrow fissure in which the mouth is situated. They are all alike, 

 short and equal, formed of a single thick stump armed with a 

 bundle of bristles (fig. 10) that project very little beyond the 

 margin, and are all glued together by a sort of albuminous mem- 

 brane. There did not seem to be any cirrus above the foot, but 

 at the roQt of each of them underneath there is a cirrus shorter 

 than the foot itself, and with a large bulb at the base (fig. 11), 

 The bristles are of three kinds : viz. (1.), the spinous (fig. 12), 

 sharp and fashioned like a needle ; (2.), the forked (fig. 13), which 

 are filiform with a bulbous root, and cut into two scarcely equal 

 prongs at the apex; and (3.), the clawed (fig. 14), a bristle which 

 has a stem slightly incrassated upwards, where a strong curved 

 and sharp claw is articulated by an oblique joint. The forked 

 bristles are the most numerous ; and I did not observe more than 

 one clawed bristle in each foot, but there were two or three from 

 which the claw appeared to have been broken away. There are 

 no anal styles. 



For the only specimen of this singular worm that I have seen, I 

 am indebted to Wm. Thompson, Esq. of Belfast. It is half an 

 inch in length, with a breadth fully one half of the long diameter. 

 It has at first glance more resemblance to a Doris than to any 

 Annelide ; and when it was placed under a common magnifier, it 

 was compared, aptly enough, to the Cyprcea europcea, the compa- 

 rison being suggested by the similarity in the ridges that cross 

 the back. 



The description, I am aware, is in several respects imperfect, 

 but from the distinctness of the worm as a species, it is assuredly 

 sufficient for its future recognition. Observations on living in- 

 dividuals seem necessary to ascertain the number and nature of 



