REPORT ON THE CIRRIPEDIA. 4.") 



truncated, almost parallel to the occludent margin. Maxilla; with stronger spinee 

 above and slenderer spines beneath the notch, which itself is without spines. Caudal 

 appendages with numerous long bristles on their summits. 



General appearance — Capitulum rather compressed, in the largest specimen narrower 

 than in the smaller ones. Fig. 8 (PL I.) represents one- of the smaller ones. Valves 

 white, almost entirely smooth, when seen with a lens there appear fine striae radiating 

 from the umbones. Peduncle very short. 



Scutum. — Apex pointed, ridge running to the umbo faint ; basal margin very short, 

 • •;i lino-tergal margin of a curious concave shape, being hollowed out for the reception of 

 the widened part of the carina; angle formed by the basal and the carino-tergal margins 

 very sharp. A very characteristic swelling is described where the scutum and the carina 

 meet near the basal margin. There is no trace of an internal basal rim, and the teeth near 

 the umbo are not very strong. The convexity of both valves is quite equal. 



Tergwm with the occludent margin straight and the basal angle truncated, almost 

 parallel to the occludent margin. 



Carina short, strongly curved, upper part much narrower than the lower part ; 

 externally carinated, internally — especially in the undermost part — distinctly concave; the 

 basal and broadest part forms a kind of fork, which is not embedded in the membrane 

 of the peduncle (PL VII. fig. 6). 



Peduncle very short, about one-eighth the length of the capitulum, indistinctly ringed. 



Mouth. — Labrum with a row of very small teeth on the crest and palpi, with a tuft 

 of slender hairs internally. Mandibles with four teeth and an inferior apex, which, 

 when seen under the microscope, terminates in three very small points. In the only 

 specimen, the mouth of which I have investigated, the mandible of the right side is 

 formed as figured in PL I. fig. 9, that of the left side (PL VII. fig. 7) having three 

 teeth only, the fourth forming with the inferior apex a single process terminated by 

 several small teeth. Maxilla (P\. I. fig. 10) with three stronger spines on the upper angle ; 

 the notch or depression beneath the angle bears no spines ; beneath the depression four 

 slender spines are inserted, the inferior upraised part is armed with a double row of longer 

 and stronger spines. The surface of the maxilla towards the side bearing these spines 

 is furnished with numerous slender hairs, of which, as a rule, two, three, or four, stand 

 close to one another. 



Cirri — Posterior cirri with segments bearing the same number of cirri as in 

 Pcecilasma kaempferi, Darwin, viz., five pairs, the lowest pair being very minute ; the 

 segments elongated. First cirrus standing not far from the second (PL II. fig. l), rami 

 nearly equal, truncated at the extremity, rather thick. Second cirrus more than twice as 

 long as the first, anterior ramus not thicker, but considerably shorter than the posterior 

 ramus ; the difference in the number of segments (18 and 15) being by no means so great 

 as that in the length of the different segments. 



