COLURID^E. 105 



Length. From hood to ends of lorica, -^^ inch ; foot and toe, ^ v inch ; total, T |j 

 inch. Habitat. Marine pools at low tide (P.H.G.). 



C. DACTYLOTUS, GoSSe, Sp. 110V. 



(PL XXV. fig. 12.) 



[SP. CH. Lorica wide in front, shallowly tubular behind, without 2)oints; foot very 

 short but wide, ; toes thick, large, and curved. Marine. 



A somewhat thickset form. The lorica is ovate, viewed dorsally, with a broad an- 

 terior gape, out of which what seems another shelly valve projects, connected by an 

 involute joint with the lorica (as seen in fig. 12a), a sort of hood, protecting the ciliate 

 front and answering to the usual hooked plate, but of very different form. The front 

 consists of several fleshy eminences (fig. 12) bearing vibratile cilia. 



The lorica ends behind in a short truncate tube, through which the foot finds exit. 

 This is exceedingly short and inconspicuous, though broad ; the toes are furcate, thick 

 at their base, blunt-pointed, and slightly decurved, when seen laterally (fig. 12a). 



I have seen but a single example, in sea-water from tide-pools near Taymouth. 

 P.H.G.] 



Length, T | 5 inch. Habitat. Marine pools (P.H.G.). 



C. PEDATUS, Gosse, sp. nov. 

 (PL XXV. fig. 13.) 



[SP. CH. Lorica cleft behind, ending in two square points ; foot stout, long ; toes 

 minute, straight. Marine. 



Two examples of this little insignificant species occurred in water sent by Mr. Hood, 

 from the Tay Firth marine pools. They were both in the same live-box as C. dactylotus. 

 The thick foot-joints and the very small toes forming a small cone, when closely appressed 

 as they usually are, will distinguish the species from all others. It is somewhat less than 

 its congener just named. I detected nothing in it worthy of record besides. P.H.G.] 



Length. About ^^ inch. Habitat. Marine tide-pools; rare (P.H.G.1. 



C. CO3LOPINUS, Gosse, sp. nov. 

 (PL XXVI. fig. 4.) 



[SP. CH. Toe very long and slender, consisting of a narrow plate laid within a 

 similar, but wider plate, and closely appressed to it. Marine. 



In the form of the toe we have here an example, quite unique in this genus, of the 

 structure which characterises the genus, hence named Cceloptts, in the Rattulidae. The 

 toe consists first of an extremely long, tapering, hollow, thin plate of transparent chitine, 

 such as would be presented by the bowl of a glass spoon, if drawn out to excessive length 

 and tenuity. Then suppose a similar plate of glass, but narrower throughout, to be laid 

 in the hollow of the former, fitted exactly to it, and reaching its taper point far before the 

 other. What is the relation of the one spine to the other, and of both to the body ; what 

 their functions, what their movements, separately or conjointly, I know not. I have 

 met with but one example, and that a dead and nearly empty lorica. The occurrence of 

 such is often of great value. It is true that it may give little or no information of the 

 internal structure, and, of course, none of manners. But of the external form and its 

 appendages, composed of undissolved chitine, we can often obtain views of beautiful 

 clearness, given with a minute precision that we can seldom hope for from a living 

 animal. For the object is perfectly still, and remains so as long as we choose, while it 

 is generally feasible to make it revolve in various directions by producing mechanical 



