(1964) first proposed that the proper spelling of this phy- 

 lum is Sipuncula, familiarly known as sipunculans. This 

 usage has been accepted by specialists but has been slow 

 to spread throughout the biological community. 



The five species found in the area between Maine and 

 Virginia to a depth of 200 m are all common forms, four 

 of them being found in all major oceans. One, P. gouldi. 



is endemic to the Atlantic coast of the United States and 

 is rare south of Long Island. Onchnesoma steenstrupi 

 and Golfingia catharinae are common on the continen- 

 tal slope but occasionally occur on the outer shelf 

 southeast of Long Island. Because they are restricted to 

 the outer shelf and occur there only infrequently, they 

 have not been included here (see Cutler 1973). 



KEY TO THE SIPUNCULA, MAINE TO VIRGINIA 



This is an artificial key designed only for the identification of the five inshore species found in the area covered by 

 this manual. Accurate identification requires a well-preserved, entire organism with the internal parts intact. If the in- 

 trovert is not fully extended, the nature of the tentacles can usually be determined by dissection of the retracted in- 

 trovert. Measurements given are trunk lengths of average adults. 



1 Trunk surface with chitinized epidermal structures (holdfasts) as in Figures 1A and 2A; one 



nephridium; irregular gut coils (Fig. 2B IGC); usually living in mollusc shell; 3-15 mm . . Phascolion strombi 



1 Trunk surface without chitinized epidermal structures; two nephridia; regular double helix of 



gut coils (Fig. IB); usually living in sediment 2 



2 (/) Longitudinal body musculature separated into distinct bundles (Fig. 3A); common in shallow 



subtidal waters; up to 130 mm (Fig. 3B) Phascolopsis gouldi 



2 (/) Longitudinal body musculature forms continuous sheet; rare in water less than 10 m deep 



3 



