OBSERVATIONS OF DR. LACHMANN. 



41 



animal whose contents are thus sucked out gradually collapses and dies ; 

 many become liquefied when only a little of the chyme is extracted from 

 them, others still live for a long time ; in large animalcules, such as 

 Stylonychia mytilus, Paramecium aurelia, &c., the sucking often con- 

 tinues for several hours. 



Fig. 17. 



Acineta tuberosa (Ehr.), attached to a stalk of Ceramium diaphanum. The specimens marked 

 a and $ are fully expanded ; y, side view of ditto ; in S the tentacula are seen in a partially, and 

 in /3 in a fully contracted state. The three figures upon the opposite side of the stem of Cera- 

 mium represent Acineta mysticina. 



(84.) A numher of roundish corpuscles, sometimes coloured, some- 

 times colourless, are generally found to occur diffused through the 

 parenchyma of many Infusoria, which were considered by Ehrenberg as 

 ova or spawn. The actual production of young from these corpuscles 

 has, however, never yet been observed ; and they are now believed to be 

 nothing more than chyme-globules, which make their appearance after 

 the digestion of food, as in the instance of the Acineta above-men- 

 tioned. 



(85.) A coloured gastric juice has been described by Ehrenberg as 

 existing in the gastric cavities of some Infusoria. The colour has, how- 

 ever, been accounted for by Siebold as produced by refraction and the 

 presence of aggregations of pigment-granules. According to Professor 

 Henfrey the reddish-violet colour is real, and arises from the presence 

 of solution of the chlorophyll of certain Oscillatorice. 



(86.) Two other organs remain to be mentioned which are common 

 to all the Ciliated Infusoria, namely the " contractile space " and the 

 " nucleus" 



