170 Mr. H. J. Carter on the Conjugations of 



poda, as my papers will show. Even the green or chlorophyll- 

 cells found in the latter (e. g. Difflugia pyriformis and Acantho- 

 cystis turfacea, and even brown in D. comjiressa) must be con- 

 sidered the analogue of the endochrome in the former, if indeed 

 the zygosis and formation of a capsuled body may not also be re- 

 garded as analogous respectively to the conjugation and formation 

 of the sporangium (see my figures of Euglypha, 'Annals/ ser. 2. 

 vol. xviii. pi. 5, and vol. xx. pi. 1) while the skeleton or organ of 

 all is internal, at least so long as the pseudopodia coalesce exter- 

 nally, as they certainly do in some Foraminifera (e. g. Operculina). 



It is true that most of the Rhizopoda extemporize stomachal 

 cavities in their sarcode for the reception of crude material, 

 which their prehensile power enables them to catch and incept 

 from the exterior, out of which they extract the nutritive parts, 

 and eject the rest. But one group of them (viz. the Acinetina) 

 nourish themselves by sucking out from the interior of other 

 Infusoria material which requires nothing but the process of 

 assimilation to turn it to their purposes, and therefore these, 

 apparently, have not even the rudiment of a stomach ; while a 

 step further brings us to the condition of the Diatomese, which, 

 like plants, derive their nourishment from the same kind of 

 material in a still more elementary form, dissolved in or dissemi- 

 nated through the medium in which they live. (I once, for two 

 years kept a species of Chora in health and vigour by repeatedly 

 adding dead grasshoppers to the water of the jar in which it 

 lived, each time that it grew pale, when the deep green colour 

 of the chlorophyll was restored, and it began to sprout briskly.) 



Although the endochrome of the Diatomeae may not be iden- 

 tical in composition with chlorophyll, still it is strictly analogous 

 to it in other i*espects. Indeed so far does this extend that 

 there is a large species of Gyrosigma in the marshes of the 

 Island of Bombay (figures of which I have preserved) that has 

 four narrow bands of endochrome arranged spirally throughout 

 its interior, identical with the arrangement of those of Spirogyra; 

 while the currents of the sarcodal threads internally in Surirella, 

 being equally identical with those of the cell of Spirogyra, 

 closely ally the Diatomese to Spirogyra, to say nothing of their 

 identity also in the process of conjugation. Then, again, the 

 filaments of Spirogyra, when thrown confusedly into a basin of 

 water, soon arrange themselves into regular parallelism, in which 

 state also they are continually changing their position, and thus 

 affording evidence of their power of locomotion. Closterium, 

 among the Desmidiese, also can attach itself by one of its ends 

 to the vessel in which it may be kept, and give proofs of a loco- 

 motive power by constantly swaying the other extremity round 

 in circles. The Euglence can attach themselves to objects by 



