560 PROCEEDINGS OP THE NATIONAL MUSEUM. vol. 39. 



TOXOMETRA, new genus. 



Centrodorsal small, the cirrus sockets in three closely crowded 

 alternating rows. 



Cirri XVII-XXIX, 9-12, in general resembling those of Antedon. 



Calyx and brachial structure essentially as in Antedon, but the 

 ossicles have very strongly produced and serrate distal ends. 



Lower pinnules somewhat stiffened; P3 is the longest, and Pj is 

 shorter than Pg; P4 is slightly longer than Pj, and P5 is slightly longer 

 than Pii the distal pinnules are about as long as Pj. 



Genotype. — Toxometra paupera, new species. 



TOXOMETRA PAUPERA, new species. 



Centrodorsal small, low hemispherical or thin discoidal, the bare 

 dorsal pole about 1 mm. in diameter; cirrus sockets arranged in three 

 closely crowded alternating rows. 



Cirri XXII, 11-12 (usually 11), 7 mm. long; first segment short, 

 second twice as broad as long, third one-third to one-half again as 

 long as broad, fourth about twice as long as the median diameter; 

 fifth not quite so long as the fourth; following segments gradually 

 decreasing in length, the antepenultimate being about one-third longer 

 than broad and the penultimate only slightly if at all longer than broad; 

 third and following segments slightly constricted centrally with rather 

 prominent ends, this character gradually dying away distally; fourth 

 and following with a slight serrate production of the distal dorsal 

 edge, but not sufficient to appear in lateral view as a definite process; 

 opposing spine prominent, though small, terminal or subterminal, 

 slightly longer than the penultimate segment, rather slender, mod- 

 erately and evenly curved. 



Radials even with the edge of the centrodorsal; IBri short, oblong, 

 three times as broad as long, just in contact basally, the anterior 

 border rather prominently everted, and with a prominent dorso- 

 ventrally elongated tubercle occupying the outer half or two-thirds 

 of the median line; IBrg almost triangular, about twice as broad as 

 long, the lateral edges about one-half as long as those of the IBrj, 

 the anterior edges, like those of the IBrj, strongly everted and very 

 finely serrate, and with a very prominent dorso-ventrally elongate 

 tubercle in the proximal two- thirds. 



Ten slender arms 80 mm. long; first brachial slightly wedge-shaped, 

 twice as broad as the median length, interiorly united for the basal 

 half, the inner sides diverging at a right angle beyond the farthest 

 point of union; the distal edge is everted and there is a median 

 tubercle in the distal half as on the TBt^; second brachial about the 

 same size, but much more obliquely wedge-shaped; the distal edge is 

 strongly everted and there is a median tubercle in the proximal half; 

 third and fourth brachials (syzygial pair) slightly longer interiorly 



