143 



This appears undoubtedly to be an undeveloped specimen of A. longicirra\ the cirri are 

 more slender than in the type, and are composed of relatively longer segments, and the ornament- 

 ation of the elements of the IBr series and iïrst two brachials is scarcely more than indicated. 



Pterometra A. H. Clark. 



Key to the Species of the Genus Pterometra. 



a 1 No ventral spines on the longer proximal cirrus segments: cirri numerous, 

 XXX — XXXV, composed of 80 — 122 segments; 20 arms; no tracé of carination 

 on the division series 



b 1 cirri excessively long and stout, from one fourth to one third again as 

 long as the arms (100 mm. to 118 mm. long), composed of 109 — 122 

 segments; all ten columns of cirrus sockets closely crowded against each 



other; arms 90 mm. long (Philippinelslands) magnipeda 



b 2 cirri shorter and more slender, from three fourths to four fifths of the 



arm length (75 mm. to So mm. long), composed of 80 — 85 segments; 



columns of cirrus sockets separated interradially by a broad shallow 



grooye, radially by a narrow flat bare area ; arms 100 mm. long (Gul f 



of Martaban to Da mar Island and the Philippines) . . pulcherrima 



a 2 Longer proximal cirrus segments bearing on the midventral portion of the 



distal edge long sharp spines vvhich extend over the bases of the succeeding 



segments; cirri XX — XXX (usually XX — XXV), composed of 70 — 1 1 3 segments; 



20 — 30 (typically about 30) arms 



b 1 proximal portion of the animal very broad, the division series and arms 



as far as the seventh brachial (at least) as seen in lateral view diverging 



rapidly, at an angle of approximately 90 ; colour, in alcohol, uniform brown 



c 1 cirri shorter, more numerous, and more slender, XXX, 86, 50 mm. 



long; arms 80 mm. long (Philippine Islands) splendida 



c 2 cirri longer, less numerous, and stouter, XX — XXV, 99 — 113, 



ö 



mm. long (northern Celebes) venusta 



tl —& 



b 2 proximal portion of the animal very narrow, the division series and arm 



bases as seen in lateral view diverging very slowly, at an angle of about 



45 ; colour in alcohol violet, blotched and variegated with white; 20 — 30 



arms (Philippinelslands) trichopoda 



1. Pterometra venusta A. H. Clark. 



A. H. Clark. Zool. Anzeiger, vol. 39, 1912, N° 11 12, p. 424. 



Stat. 117. Entrance to Kwandang Bay, Celebes. 80 Metres. 4 Ex. 

 The centrodorsal is thick discoidal or columnar, the sides nearly parallel, 6 mm. broad 



