1922] Essenberg: Stylarioides PapUlosa 371) 



STYLARIOIDES PAPILLOSA, SP. NOV., 



A NEW ANNELID FROM THE 



SAN DIEGO REGION 



BY 



CHRISTINE E. ESSENBERG 



The polychaetous annelids of the family Stylarioidae are appar- 

 ently rare in waters of the Pacific Coast of North America. The large 

 annelid collection of the University of California at Berkeley does 

 not contain any specimens of this family. 



In the San Diego region, where shore collections are frequently 

 made at low tide, a single specimen has thus far been found by the 

 author and is evidently a new species which we designate Stylarioides 

 papulosa. 



This species is of a gray-brown color and is difficult to detect in 

 mud where it lives, except by its wriggling motion. The body is 

 about 70 mm. long, slightly flattened on the ventral side, tapers 

 gradually toward both ends, and terminates bluntly at both. Tt has 

 forty segments, which are visible only from the ventral and lateral 

 surfaces. On the convex dorsal surface they are obscured by the 

 abundance of long, finger-like projections (fig. 1). The mouth is 

 surrounded by two long, green palps and by fourteen or more grass- 

 green, long branchiae (figs. 1, 2). The parapodia are long in the 

 living animal, with short papillae projecting even from their tips. 

 In the preserved specimen the parapodia have contracted very much, 

 so that they are hardly visible from the dorsal surface. There are 

 two kinds of setae. The ventral setae, about two on each parapodium, 

 are conspicuously large, compound, and hooked (figs. 3, 4, 6). The 

 dorsal setae are long and slender. They are hardly visible in the 

 living animal, being buried deeply in the parapodium (fig. 2). The 

 dorsal projections, or villi, giving the animal a rough or spiny appear- 

 ance, are of two kinds. Some are long, finger-shaped, attached to the 

 body by a narrow neck (fig. 5) ; others are smooth and uniform in 

 shape (fig. 8). These villi-like projections incline posteriad and 

 between them are lodged grains of sand and mud, giving the animal 

 the appearance of a moving piece of mud. 



