INVERTEBRATA, CRYPTOGAMIA, MICROSCOPY, ETC. 285 



have two or three attached to it in this way, the final result being a 

 sort of network. The species thus affords an example of the least 

 modified form of compound animal or " stock " ; the connection of the 

 various i:)ersonEe forming it being of the loosest description. 



The lorica attains a length of O'l mm., and presents a basal 

 portion narrowing gradually to the attacliment of the slender stalk, a 

 middle portion consisting of three distinct rings, and a distal, somewhat 

 expanded portion. The colour is yellow in young specimens, gradu- 

 ally deepening in the adult to dark bro^n. 



The peristome (p) and disc (jpcl) present the usual characters, but 

 there is, in addition, a special circular lobe of the peristome on the 

 mouth side, which acts as an operculum (op), shutting in the whole 

 animal when retracted. 



Gruber's observations on the structure usually described as a 

 bristle-like cilium (Fig 9, M), overhanging the mouth on the outer 

 side, are of great interest. He states that this is not a cilium at all, 

 but a very delicate, transparent, tolerably stiff membrane, attached to 

 the inner edge of the peristome, and bounding the mouth externally 

 as an outwardly sloping wall, highest immediately opposite the mouth, 

 and gradually sloping away on either side. The author considers that 

 this structure is of considerable functional importance ; all particles 

 directed by the cilia of the disk against it, are immediately carried 

 directly into the oesophagus ; all others are whirled away from the 

 animal.* 



G. Cothurnia operculata (Figs. 10, 11, and 12). — As in C. socialis, 

 the lorica presents a constricted neck, and at the constriction is a 

 circular valve or_^operculum (Figs. 10 and 11, op), not as in the former 

 species a prolongation of the protoplasm, but evidently made of the 

 same delicate transparent substance as the lorica itself, to the inner 

 surface of which it is attached. In empty loriciB the operculum is 

 always oi)cn, so that its closure must be due to the contraction of the 

 animal. There is, in fact, attached to its under surface, one end of 

 a delicate cuticular membrane (Figs. 10 and 11, rt), bent longitu- 

 dinally into a half cylinder and with its other end embracing the 

 proximal extremity of the animal. When the latter retracts, the 

 membrane is pulled upon and the operculum closed. The membrane 

 is so delicate that under ordinary circumstances all that can be seen of 

 it are its edges, which look like two delicate threads passing from 

 the base of tlic animal to the operculum. 



In the extended condition the protoplasm shows a fine transverse 

 striation. 



Glycogenesis in Infusoria, &c.t — According to Claude Bernard f 

 the glycogenic function is a general one to be found wherever there 

 is nutrition, and he affirmed its existence not only in the liver of 

 Vertebrates, but in MoUusca, Crustacea, Worms, and Insects. M. 



* This membrane seems to perform much the snmo part in nutrition as the 

 "collar" of HagcUatcs, and it seems not improbable that the two structures may 

 be morphologically identical. f 'Comptes Rondus,' xc. (l!SSO) p. 77. 



X ' Lemons 8ur Ics I'heuomcncs dc la Vie Coinmuna iiux Auimaux tt aux 

 V^getaux.* Paris, 1878-9. 



