164 Dr. G. C. Wnllich on the Ti/pe 



that '^ sometimes Amoeba puts forth a lew broad lobated ex- 

 pansions ; sometimes these are more numerous, slender, and 

 elongated, a^su}nin(j a radial direction ; and oecasionally they 

 are so greatly multiplied, radiate, with such regularity^ and 

 taper so uniformh/ from base to apex, as strongly to resemble 

 the pseudopodia o/' AcTiNOPHKYS." 



This is undoubtedly true; and I therefore leave Dr. Carpenter 

 to reconeile the fact "with his classification and definitions of 

 the orders, of whicli I now subjoin a summary, taken from his 

 paper in the ' Xatural-llistory lleview ' to which reference 

 has already been made *. 



Dr. Carpenter's Arrangement of the RiilZOPODA. 



I — 



LoBosA. Eadiolaria. Rkticularia. 



.Amaebina, Actinophrifina. Gromida. 



AcaHthunietrina. Furaminifera. 

 '•...'■ Polycystina. \ 



Thalussicollina. \ 



Inftjsoeia. Gbegarunida. Spongiada. Pbotophyta. 



After saying that " any small separated portion of the 

 sarcode body of the Ehizopoda will behave itself after the 

 characteristic fashion of its type " (that of Arcella behaving 

 like that of Amoeba, that of Polysfomella, or any other of the 

 Foraminifera, like those of Grojnia), and adding that "this 

 fact seems to him to afford an additional justification of the 

 employment of the characters furnished by the pseudopodia 

 as the basis of a systematic arrangement of the class," he in- 

 forms us that the characters of the three orders into which 

 he proposes to distribute its various forms may be concisely 

 summed up as follows : — 



" I. Eeticularia. — The body composed of homogeneous 

 granular protoplasm, without any distinction into ectosare and 

 endosarc ; neither nucleus nor contractile vesicle ; pseudopodia 

 composed of the same substance as the body, extending and 

 multiplying themselves by minute ramification, and inoscu- 

 lating completely wherever they come into contact ; a con- 



• It may be well to bear in mind that the article in the * Review ' ap- 

 peared in iSGl aa an avant-courier to the * Introduction to the Study of 

 the Foraminifera/ which appeared just a year afterwards. The tabular 

 classification of the Rhizopods is taken from page 17 of the latter 

 work. 



