266 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 10 



Family Opheliidae 

 Key to Species 



1. Some parapodia provided with elongate cirri or also other sensory 

 structures 2 



1. Parapodia reduced throughout, without special sensoiy struc- 

 tures ; body spindle shaped, resembles small Amphioxus . . . 

 Polyophthalmus pictus 



2. Body spindle shaped ; without a ventral, longitudinal groove ; 

 with dark eyespots between some successive parapodia . 

 Armandia biociilata 



2. Body thicker ; with a ventral, longitudinal groove ; without dark 

 eyespots between successive parapodia 3 



3. A sharp constriction between head and thoracic region ; a pair of 

 conspicuous lateral ridges between the prebranchial and bran- 

 chial regions 4 



3. Without a sharp constriction between these regions; without 

 thick, lateral ridges between prebranchial and branchial regions ; 

 posterior end terminates in a pair of thick, digitate lobes ventrally 

 and numerous slenderer lobes dorsally; usually with about 20 

 pairs of cirri form branchiae Ophelia limacina 



4. Some parapodia provided with a pair of cirriform branchiae in 

 addition to dorsal cirri .... Thoracophclia mucronata 



4. Some parapodia provided with branched branchiae in addition to 

 dorsal cirri Pectinophelia 5 



5. With usually 15 pairs of pectinately branched branchiae . 

 P. dillonensis 



5. With usually 16 pairs of irregularly, pinnately branched bran- 

 chiae P. luilliamsi 



Polyophthalmus pictus Dujardin 



Fauvel, 1927, p. 137, fig. 48. 



This occurs throughout areas in the vicinity of Dillon Beach, along 

 rocky shores. It is especially abundant just below the Fucus zone, at 

 moderately low water line, among algae. It resembles a minute Amphi- 

 oxus. Length is 10 to 20 mm. 



