2. Dichelaspts Tydcmani n. sp. PI. II, fig. 8 — 13. 



Capitulum much compressed willi the ape.x highly produced. Scuta with the basal segment 

 triangular and the occludent segment broad, having the .shape of a scalpel ; terga with the lower 

 part about as wide as the occludent segment of the scuta; carina much bowed, terminating in 

 a disc, notched at its extremity. 



General appearance (PI. II, fig. 8). Capitulum compressed, flat. Valves not very 

 close too-ether. Valves thin and translucent, carina perfectly, other valves very imperfectly calcified. 

 The membrane covering the valves with rather long hairs. 



Scuta (fig. 9). The occludent segment is long, flat, pointed at its extremity; its 

 occludent margin is straight, the carinal margin convex, whence the shape of the segment is 

 that of a scalpel. The basal segment is triangular, small; only a small part of the valve is 

 •calcified: it stretches from the lower point of the occludent segment to one fourth of its length; 

 what mio-ht be called the junction of the two segments is calcified, but no calcification is seen 

 in the basal segment itself. 



Terga (fig. 10). Scutal margin excised at a point vis a vis the apex of the scutum; 

 the excision separates a smaller occludent projection from a larger carinal projection or lower 

 part. Occludent margin simply and slightly curved. Incipient calcification at the umbo, where 

 the valve shows an indistinct third prominence. 



Carina (fig. 11). Much bowed, narrow, long. The basal end is rectangularly inflected 

 and .stretches internally to about the half of the diameter of the peduncle. The whole valve is 

 calcified; the basal portion is slightly wider than the upjjer part and is excised at its extremity. 



Peduncle narrow, especially close under the capitulum; about -\J^^ the length of 

 the capitulum. 



Size. Very small, the capitulum measuring not quite 2 nuu. in length. 



Mouth. Labrum bullate. Mandibles (fig. 12) with four teeth and the inferior 

 angle tooth-Hke and acuminated. Maxillae (fig. 13), with three larger spines at the upper 

 angle, beneath which there is a triangular incision or notch, bearing two slender hairs. The 

 edge beneath this notch is straight and projecting, and bears six or seven unequal but rather 

 large spines. 



Cirri. First pair short with the rami very unequal: the longest has five, the shortest 

 four seo-ments; the segments are nearly quadrangular with the exception of the first which is 

 elongated; terminal segments small and blunt. Segments not thickly clothed with hairs or bristles; 

 these are placed somewhat irregularly. 



The other cirri have very long and slender segments, bearing three pairs of spines 



as a rule. 



The caudal appendages are extremely slender but not longer than half the length 

 of the pedicels of the sixth cirrus. They bear a few (about four) very delicate hairs at their ends. 



The specimens are attached to long, yellowish-brown hairs or spines, which are hollow 

 and bear triangular pointed teeth placed in irregular rows. They were taken, October 1899, 

 near Saleyer anchorage, at a depth of 10 — 25 m. 



24 



