CLAPAREDE AND LACHMANN, 1858-1860. 23 



which indeed finally established the claim of these remarkable animalcules 

 to hold rank as the members of a distinct order of the Infusoria, was 

 brought forward by the last-named investigator in conjunction with Edouard 

 Clapar^de, in three extensive essays, published in volumes v. to vii. of the 

 ' M^moires de I'lnstitut Gcnevois,' extending over the years 1858 to i860. 

 These three memoirs, derived from the joint work of the above authori- 

 ties, both co-workers in the laboratories, and disciples of the eminent 

 Johannes Miiller, form, as issued more recently in a single volume, the well- 

 known ' Etudes sur les Infusoires et les Rhizopodes,' containing collectively 

 over seven hundred pages of text, and thirty-seven quarto plates, constantly 

 referred to in these pages, and which holds rank as one of the most complete 

 and important contributions to the literature of the present subject as yet 

 extant. That portion of the volume above quoted which relates more 

 especially to the organization of the Acinetse, proving the same to be 

 entirely independent of the Vorticellidae, and thus reversing the verdict of 

 Stein, is embodied chiefly in the so-called third part of the * Etudes.' 

 Actually, however, this section of the work was published the first of all, its 

 substance being included in the conjoint prize essay communicated to the 

 Paris Academy of Sciences in February of the year 1855. The scheme 

 of classification adopted by Claparede and Lachmann is submitted in its 

 fully extended state later on, but may be briefly referred to here as 

 comprising the ordinary infusorial orders of the Ciliata and Flagellata, two 

 smaller groups of similar value being, however, instituted, the one entitled the 

 Suctoria for the reception oi Acineta,Podophrya, and all corresponding forms 

 in which prey was seized and incepted through the medium of tubular and 

 suctorial tentacle-like appendages, while that of the Cilio-flagellata was 

 proposed by the same authorities for the distinction of Peridinimn and 

 various associated types which have as locomotive organs a girdle or other 

 supplementary series of fine vibratile cilia, in addition to one or more 

 flagellate appendages. 



Claparede and Lachmann's interpretation of the organization and 

 affinities of the Infusoria, for which, however, the first-named writer would 

 appear to be chiefly responsible, is altogether opposed to the unicellular 

 one of Von Siebold. While conceding to these organisms a separate and 

 even the lowest position in the animal scale, they proposed to regard them as 

 approximated most nearly, on the one hand, to the Coelenterata, and on 

 the other, more remotely, to the lower Annelids. In accordance with 

 the views of these Geneva anatomists, the Infusoria were, in short, repre- 

 sented as possessing a well-defined body-wall, the softer internal area 

 enclosed and bounded by which constituted an equally distinct chyme- 

 filled somatic or gastric cavity. A very considerable accession to the 

 number of known forms of animalcules, and more especially as relates to 

 the previously little studied marine types, e. g. genera Freia {Follicularid), 

 Tintmmis, and Peridinmin, was effected through the indefatigable labours 

 of Claparede and Lachmann, while the evidence accumulated by them 



