THE HERMIT CRABS OE THE PAGURUS BERNHARDUS 



TYPE. 



By James E. Benedict, 



First Aifxistaid Curator, Dirmon of Marine Invertebrates. 



It i.s the purpose of this paper to bring to notice that section of the 

 genus Pagurus of which P. henihardm is the type. 



Pagurm hernhnrdnH occurs in the shallow waters of northwestern 

 Europe, and is represented by P.acadianus in the waters of northeast- 

 ern North America; hy P. alad:e/ms, P. aleuticm, and P. ochotemis 

 in the waters of the northwest coast; by P. patagoniensis and P. 

 harljajci' in Patagonian waters. 



Of these species P. acadianuH and P. alaskemis are more nearly 

 related than any others. Next is P. hernha/rdus, more closely related 

 to the former two species than to P. aleuticus, which, in turn, is much 

 more closely related to the first three than to the spiny-handed forms, 

 P. ochoteiisk^ P. patagoniemis. and P. Imrhiger. 



In the author's opinion the validity of the specific distinctions made 

 can only be contradicted, if at all, after more collecting has })een done 

 in intermediate localities, when it is possible that the more closely 

 related American forms may be reduced to subspecies. 



KKY TO THE SPECIES. 



ff. Hands granulated. 



h. Width of the left hand at base less than one-half of its length 



bernhardufi (p. 452) . 

 //. Width of the left hand at l)ase one-half of its length. 



c. Dactyles of the ambulatory feet not grooved on outer margin. 



d. Acicle slender, without serrate outer edge acadianus (p. 454). 



d. Acicle broad, edge serrate alaskensis (p. 456). 



'•. Dactyls of the ambulatory feet with a deep groove on the outer margin 



aleuticus (p. 460). 

 a. Hands spiny. 



h. Spines of the liauds without ))lack points ochoten.vx (p. 463). 



I>. Spines of the hands with black jjoints. 



r. Antennules niucli longer than the eyes patagonienm (p. 465). 



c. Antennules not as long as the eyes barbif/cr ( p. 466 ) . 



Proceedings U. S. National Museum, Vol. XXIII— No. 1216. 



451 



