232 THE AMPHINOMID.E, APHRODITID.E, POLYNOID/E, AND SIGALIONID^ 



Genus HALOSYDNA, Kinhenj. 



Body linear oblong ; head continuous anteriorly with the bases of 



the median and lateral tentacles. 

 Eyes large. Palpi smooth. Nuchal collar with a prominent flap. 

 Segmental eminences distinct and the papilhie long. 

 Proboscis, with twenty-two frilled papillte along each border. 

 Elytra, eighteen pairs, large, soft, and with a frilled outer border, 



not covering the dorsum. 

 Notopodium minute, with slender, simple, and finely spinous chsetse. 

 Neuropodium rather long, with numerous somewhat slender chsetse 



with tips of varying breadths. 



*Halosydna gelatinosa, M. Sars. Size to 3| inches. 



Genus ACHOLOE, DelU Chiaje. 



Head elongated from before backward and running into the bases 



of the tentacles. 

 No peaks. Four large, equidistant eyes. Palpi smooth and short. 

 Body sublinear, flattened ; segments numerous. 

 A segmental eminence, but no distinct papilla. 

 Cirri on every foot, and a T-shaped branchial process. 

 Elytra numerous. 

 Parapodia short, notopodium minute, chaitee few and small, with 



a minute hook at the tip. Neuropodium bearing chastai with 



long and strong shafts and short spinous regions having a sharp 



hook at the tip. 



*AcH0L0i5 ASTERICOLA, Delle Chiaje. Size to 2 inches or more. 



Genus LEPIDASTHENIA, Malmgren. 



Corpus elongatum, sublineare depressum. 



Oculi 4, utrinque bini approximati, laterales, par anterius in vel 

 pone medium lobi cephalici. 



Antennae una cum tentaculo e parte anteriore lobi cephalici productaB. 



Elytra minuta posteriora versus magnitudine decrescentia, maximam 

 partem dorsi nudam relinquentia, in segmentis pedibus instructis 

 1, 3, 4, G, 8, . . . 20, 22, 25, 28, . . . 79-82 obvia. 



Ptamus superior pedis perminutus acicula sola pneditus, setis 

 omnino carens. Setse rami inferioris infra apicem subrectum 

 bidentatum, dentibus subrectis, paullo dilatatjie serrulata3 ; 1 1. 2 

 superiorum ceteris plerumque duplo validiores et crassiores apice 

 integro, margine altero vero dentibus paucis serrate. 



Cirri anales 2 breves pone^anum dorsualem. [Malmgren.] 



* LEPIDASTHENIA ARGUS, sp. nov. Size to 8 inches (see p. 250). 



