2 AMERICAN MUSEUM NOVITATES [No. 81 



true but at least Sars's description was sufficient to show that his genus 

 could not be grouped with the others above named. 



The genus about to be described seems also to belong here and yet 

 differs enough from the other genera to make its establishment valid. 

 The number and structure of the swimming legs and the number of 

 joints composing the first antennae vary considerably in the genera of this 

 family, but in none of them do we find the combination which exists 

 here of six-jointed antennas with only three pairs of swimming legs. 



Pherma, ' new genus 



Body spindle-shaped with segmentation distinctly indicated by transverse 

 grooves or lateral invaginations. Cephalon fused with the first thorax segment, but 

 with a distinct groove between the two on the dorsal surface. Fourth thoracic seg- 

 ment strongly narrowed posteriorly; genital segment with projecting convex sides; 

 abdomen made up of a single segment. Egg strings slender, eggs multiseriate and 

 very numerous. Two pairs of filiform antennae; one pair of stout, uncinate maxilli- 

 peds; three pairs of swimming legs, each biramose, the exopod 2-jointed, the endopod 

 1 -jointed. 



Type of the genus Pherma curticaudatum, new species. Monotypic. 



Pherma curticaudatum, 2 new species 



Figures 1 to 9 



Habitat and Record of Specimens. — Three adult females, one of which bore 

 egg strings, were taken from the parapodia of an unnamed annelid dredged from a 

 depth of 645 fathoms by the Bureau of Fisheries steamer ' Albatross ' off the coast of 

 Lower California in April, 191 1. These specimens are deposited in the Department of 

 Lower Invertebrates of The American Museum of Natural History (Cat. No. 4617), 

 where they become the types of the new genus and species. 



Specific Characters of the Female. — In addition to what has been given 

 tinder the genus diagnosis we may append the following. General body form cylin- 

 drical, considerably swollen, widest across the third thoracic segment. Body seg- 

 mentation somewhat indistinct but well indicated by lateral invaginations. Head 

 fused with the first thoracic segment, but with the separation of the two marked by a 

 dorsal groove. Head semielliptical and regularly rounded, one-half narrower than the 

 first thoracic segment. Antennae attached to the frontal margin on the dorsal sur- 

 face and turned backward along the lateral margins. First thoracic segment barrel- 

 shaped, one-half longer than the head; second and third segments increasing in 

 length and width; fourth segment longer than the third but not as wide, considerably 

 narrowed posteriorly. Fifth segment only one-third the width and one-seventh the 

 length of the fourth segment, forming a slender waist in front of the genital segment. 

 The latter one-third wider than the fifth segment with strongly convex sides, to the 

 center of which are attached the egg strings. Abdomen made up of a single short 



i0ep/ia, "a burden." 



*C urticaudatum, "short tail." 



