- 



Dr. A. Gruber on Protozoa. 271 



which, as already mentioned, always occurs where pseudopodia 

 are formed. This has been more strongly coloured by the 

 carmine than the underlying mass of granular sarcode. Scat- 

 tered through the latter we observe a great number of granules 

 or spherules, also dark-coloured, upon which I must here give 

 some more details. 



In all the Pachymyxce that I have examined (and there 

 were a great number of them) I have never been able to ob- 

 serve any trace of a nucleus ; but, under the right treatment, 

 the above-mentioned red points, relieved by their darker colour 

 from their surroundings, nearly always made their appearance. 

 Now it seems not improbable that the red granules represent 

 small nuclei, as, indeed, we meet with a multiplicity of nuclei 

 in other Rhizopods, in Pelomyxa for example. In favour of 

 their nuclear nature we have likewise the behaviour of the 

 granules towards reagents, and especially their rapid staining 

 by carmine ; this, however, is not a certain proof ; and, unfor- 

 tunately, I am unable to offer any such. 



In what relation these possible nuclei stand to reproduction 

 I could not ascertain j but one preparation led me to suppose 

 that they might perhaps give origin to an endogenous divi- 

 sion, or, more properly speaking, to a formation of swarmers. 

 Thus in a Pachymyxa treated as above described, but in which 

 the protoplasmic body had only become very slightly stained, 

 I met with a considerable number of dark red granules. All 

 these, however, were surrounded by a zone of hyaline proto- 

 plasm, also very strongly stained, so that they appeared like 

 small Amcebce. They lay scattered in the sarcode, just like 

 the cells formed internally during the segmentation of the ova 

 of many insects * (e. g. Gryllotalpa). 



I could never observe the issue of such corpuscles from a 

 Pachymyxa j but in my preparations I have often found 

 among the Algae very numerous little amoebiform creatures of 

 exactly similar structure, which might perhaps be related to 

 them. 



But even if a reproduction of Pachymyxa by swarm-buds 

 should actually occur, this is not its only mode of propaga- 

 tion ; for an increase by division certainly also takes place. 

 We often find specimens which are in process of breaking up 

 into two parts by a constriction taking place in the middle, as 

 iudeed might be expected a priori\. 



Finally, as regards the position of Pachymyxa in the sys- 



afterwards 



am 



t A breaking-upinto a greater number of small pieces also seems to mts 

 probable. 



