IS;")!.] 267 



Com^pedus Crustaceorum quce in Orbis Terrariini circumnavigatione, Carolo 

 Wilkes e classe ReipubliccE Faderalce Duce, lexit et descripsit J. D. Dana, 



PAGURIDEA. 



The Paguridea include two groups, distinguished by peculiarities in the form of 

 the inner antenna, outer maxillipeds, and some other characteristics ; the one 

 agnatic in habit, and the other suhterrestrial. They are as follows : 



Fam. I. Pagurid.e. Inner antenuEc short, first joint very short. Palpus of 

 maxillipeds with a multlarticulate flagellum. Aquatic or littoral. 



Fam. II. Cexobitid.b. Inner antennae very long, the first joint of the base 

 as long as the eyes or longer, and bent obliquely downward. Palpus of outer 

 maxillipeds without a flagellum. Suhterrestrial. 



The Paguridre have hitherto been divided into but two genera ; Tagnrus, with 

 unsymcnetrical abdomen, and Cancellus, (Edvv.) with symmetrical. There 

 are, however, important characteristics, which point to a division into other 

 groups. These have been partly indicated by Milne Edwards, in the subdivi- 

 sions of the genus Pagurus, laid down in his work on Crustacea,* and more 

 distinctly in the Annales des Sciences Naturelles, for July, 1848. f In the latter 

 article there are discrepancies in certain instances, between the character of the 

 species and those mentioned for the subdivisions, which we find it difficult to 

 reconcile; such as the placing of P. tibicen, and some related species, with his 

 " jEquirnanes," when, in fact, the left hand is very much larger than the right, 

 and the guttat /IS zr\A granulattis with the " Senestres," although, in the former, 

 the hands are nearly equal, as in many of the " ^quimanes," and in the latter 

 the right hand (as is observed in his "Crustaces") is actually the larger. Yet his 

 sections are, in the main, natural groups, and some of them have more important 

 points of distinction than he has mentioned. 



"The Pagiiriis Bernhardiix is the type of one of these groups. Besides being 

 "dextres," they are peculiar in having acumijiate fngers,v/yt\\ the tips of those of 

 the larger hand calcareous ; and although the feet of the 4th pair are subcheliform, 

 like most other Paguridas, the scabrous area or rasp of the hand is confined nearly to 

 the posterior edge. Moreover, thespeciesbelongmainly to colder waters, while the 

 ordinary Paguri abound especially in the tropics. All the Paguri of England (or 

 with but one uncertain exception, recently pointed out,) are of the Bemhardus 

 type ; those of the Northwest coast of America are the same. We naturally, 

 therefore, distinguish this group as a genus under the name of Bernhardus. 



Among the remaining Paguri, the larger part have the feet of the 4th pair sub- 

 cheliform, the penult joint being broad, and the last (or tarsus) forming a finger 

 placed on its anterior margin. Yet, a few have these feet vergiform, the tarsus 

 being terminal ; and these species are also peculiar, in having two pairs of slen- 

 der appendages at the base of the abdomen, on account of which they are called 

 the " Pagures appendicules '' by Edwards. Besides, they have the flagellum of 

 the outer antennae more or less hairy, and often long ciliate along the under side, 

 and, also, the inner antennae have a longer base than usual, the 2d basal joint 



* Crustaces, ii, 213, and Annales des Sci. Nat. [2|, vi, 257. 

 t Ann. des Sci. Nat. [^], x, .19. 



