558 PROCEEDINGS OF THE NATIONAL MUSEUM. tol. 39. 



Station 5510. — Two specimens, each with ten arms 100 mm. long. 



Station 5536. — Two specimens; one has ten arms 125 mm. long; 

 the other is of the same size, but has twelve arms, the two IIBr 

 series being 2. 



Station 5537.— Two nearly perfect specimens, both with arms 140 

 mm. long; both have regenerating disks; one has twelve arms, both 

 IIBr series being 2; the other has eleven arms, two IIBr 2 series 

 being present, but one post-radial series not dividing at all, the IBrj [ 

 merely bearing a pinnule instead of being axillary. | 



Genus CHLOROMETRA. 



CHLOROMETRA ROBUSTA, new species. 



Centrodorsal long, conical, about 6 mm. wide at the base and , 

 6 mm. high, the cirrus sockets confined to the mid-radial region, as in i 

 C. aculeata, where they are arranged in two very closely crowded ; 

 converging alternating columns, which merge and become a single 

 column distally; four or five cirrus sockets in each radial area. 



Cirri stout and very long, XX-XXV, the peripheral 26-28, 55 mm. 

 to 60 mm. long, becoming apically 21, 35 mm. to 40 mm. long; first 

 segment short, the following increasing in length, becoming approxi- 

 mately as long as broad on the sixth, and from the eighth onward 

 about twice as long as broad; distal dorsal edges of the segments 

 somewhat thickened, especially in the outer half of the cirri; penulti- ■ 

 mate segment slightly less in diameter than those preceding; opposing 

 spine very small, terminal; terminal claw about as long as the 

 penultimate segment, slender, slightly curved; cirri moderately 

 compressed laterally. 



Ten arms 211 mm. long; arm bases and arms essentially as in 

 C. aculeata, but much more rugged; IBrg with a prominent dorso- 

 ventrally elongate well-rounded tubercle; second brachial similar; 

 following brachials, to the fourteenth, with prominent rounded 

 median tubercles as long as the segments; after the fourteenth these 

 tubercles become high thick overlapping spines, whose bases occupy 

 the entire dorsal median line of the segments; terminally these 

 spines gradually decrease in height and eventually disappear. 



The genital pinnules are expanded as in Glyptometra. ■ 



Type.— Cat. No. 27505, U.S.N.M., from station 5348. I 



Two smaller specimens were also secured at this station; one of 

 these is about the size of the type of C. aculeata; it is easily dis- 

 tinguished by the much longer and more sharply conical centro- 

 dorsal and by the dorsal ornamentation of the arms which, though 

 not so developed as in the adult, is yet prominently marked; the 

 cirrus segments are longer than those of C. aculeata; the other speci- 

 men has arms only 55 mm. long; the dorsal ornamentation is only 

 just beginning to appear, but is already of the type characteristic of 



i 



