REVISION OF PILARGIDAE — PETTIBONE 177 



beginning on setiger 3. Pygidiiim? Proboscis not extended. Intes- 

 tine with intestinal caeca, two pairs per segment, shorter anterior 

 pair and longer posterior pair extending into notopodia. Integument 

 with scattered minute papiUae. 



A. jonesi may be distinguished from the other species of AncistrosyUis 

 as indicated in the key on page 165. It is closest to A. hamata, differing 

 by the development of the enlarged conical notopodial lobes and 

 the small median antenna. 



Distribution: Chesapeake Bay. In 7 fms. 



Genus Cabira Webster, 1879, revised 



Cabira Webster, 1879. [Type-species: C. incerla Webster, 1879, by monotypy. 

 Gender: feminine.] 



Remarks: Cabira was placed by Webster among "genera incertae 

 sedis." The brief description of C. incerta is confused, particularly 

 in regard to the parapodial rami. Fauvel (1920) referred the species 

 to AncistrosyUis among the Hesionidae, suggesting that perhaps the 

 median antenna was lost. Hartman (1947) placed it in the Pilargidae 

 and suggested that the name Cabira perhaps best be dropped, since 

 the original account is much too faulty and incomplete. 



The t3^pe of Cabira incerta has not been found in the U.S. National 

 Museum, where most of Webster's polychaete material was deposited. 

 As far as can be determined, it no longer exists. Among the pilargids 

 collected in Chesapeake Bay off Rappahanock River, dredged in 7 fms. 

 in mud by Marvin Wass, are five specimens which can be identified 

 with Cabira incerta. I am herewith revising the genus and species, 

 based on this new material. 



Diagnosis: Body subcylindrical, with parapodia poorly developed. 

 Prostomium small, with paired biarticulate palps consisting of large 

 palpophores and very small palpostyles; with paired small lateral 

 antennae (lacking in C. cax^ensis) ; w^ithout median antenna. Tentacu- 

 lar segment indistinct from prostomium, achaetous, with 2 pairs of 

 very small tentacular cirri. Parapodia poorly developed, subbira- 

 mous; notopodia represented by notoacicula and small dorsal cutI, 

 with emergent stout hooked notosetae beginning on setigerous seg- 

 ments 6-8; neuropodia small, with neuroacicula and few similar 

 neurosetae; neurosetae simple, delicate, capillary (additional short 

 setae in C. brevicirris) ; ventral cirri small, below or at tips of neuro- 

 podia. Pygidium bilobed, without anal cu-ri. Proboscis cylindrical, 

 sometimes ringed, with longitudinal basal rows of spines (in type- 

 species) or with soft papillae (C. brevicirris). 



According to this revision, Cabira includes the following: 



C. incerta Webster, 1879, p. 267. Chesapeake Bay, Virginia. 

 C. pilargiformis (Uschakov and Wu, 1962, p. 75), as AncistrosyUis pilargi- 

 formis. Yellow Sea. 



