108 THE VOYAGE OF H.M.S. CHALLENGER. 



rows, each row containing about sixteen scales. Surface of peduncle furnished with very 

 long and delicate bristles. 



Mouth. (PI. X. fig. 1), Labrum bullate, with an anteriorly projecting and rather flat 



part. Palpi robust, with very numerous hairs at the extremity and on the outer surface ; 

 their shape resembles that of the last joint of the human thumb. Mandibles with 

 three teeth, nearly equal, the first being only slightly longer than the two following 

 ones. The inferior angle broad, rounded at the extremity, which is flat and indistinctly 

 pectinated. The outer surface of the inferior angle is furnished with very delicate hairs. 

 Maxillm elongate, not very narrow. Free edge (PI. X. fig. 2) without any notch; how- 

 ever, neither straight, being slightly excavated in the superior and slightly convex in 

 the inferior half. The free edge is beset with a double row of strong spines ; the superior 

 angle shows only one great spine. It is much thicker but only slightly longer than the 

 other spines. Second maxillce with a rounded lobe at the anterior margin furnished 

 with numerous hairs. The hindermost part of the outer surface over almost the whole 

 length is also furnished with very Ions; and slender hairs or bristles. Orifice of the 

 so-called olfactory organ not placed on a long tubular process. 



Cirri. — First pair with the rami unequal ; the most anterior one has eight broader 

 the posterior ramus twelve narrower, segments. The second pair has also unequal rami ; 

 one of twenty-one, and one of twenty-four segments. The other cirri have equal rami. 

 The caudal appendages are relatively large, four-jointed, and furnished with a tuft 

 of very long hairs at the extremity. There are also rows of very long hairs on the 

 anterior margins of the other segments. 



Penis wanting. 



Eggs large (greatest diameter 1*03 mm., shortest 0'S7 mm.) ; united in two flat masses, 

 each of which contains two layers of ova, Number of eggs in each packet about 200. 



Com file mental males numerous. They have a long cylindrical shape, and are of 

 a very simple structure (PI. IX. fig. 12). In one of the full-grown specimens those 

 of the one side numbered about half a dozen, those of the other side four. I have 

 been able to study their anatomy by transverse sections. Details will be given in the 

 third part of the present report. The length of the males is about 17 mm. They are 

 covered by a mantle densely beset with very numerous spines. At the one side this 

 mantle has a slit through which the rudimentary antennae peep out, The opening of 

 the genital apparatus is at the other extremity of the little animal. The structure of 

 the genital apparatus shows the same parts as in the complemental males of the other 

 species, — testis, receptaculum seminis, vas deferens. 



Scalpellum regium (Wyv. Thorns.), n. sp., was dredged at two Stations. Station 

 61, June 17, 1873; lat. 34° 54' N., long. 56° 38' W. ; depth, 2850 fathoms; 

 bottom temperature, l° - 5 C. ; bottom, grey ooze. Station 63, June 19, 1873 ; lat. 35° 

 29' N., long. 50° 53' W. ; depth, 2750 fathoms ; bottom, grey ooze. 



