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of cells are involved in a puzzling process of conjugation. Whether 

 the two very irregulary amoeboid and elongate nuclei have resulted 

 from the division of a simple nucleus is not certain. It will, however, 

 be noticed that the three cells are connected together by one of these 

 nuclei, and two others of the three cells are joined by the second 

 nucleus, which has a pair of divergent pseudopodial processes. 



In Fig. 5, a cell is represented with two distinct nuclei. Whether 

 one of these has crept over from an adjacent cell is not known but 

 such is the suspected origin of one of them; these nuclei lie side by 

 side and are slightly flattened against each other. Whether such 

 nuclei would conjugate after having met together in an adjacent cell 

 was not determined. 



The foregoing statement of facts is founded upon material prepared 

 as follows; the fresh intestine of an adult Porcellio is slit open, 

 floated upon a slide and cleared of its contents by dropping water 

 from a pipette upon it, then stained on the slide, and mounted in 

 dilute glycerine. A number of stains were used such as methylene 

 blue, methylene blue and ammonium picrate, carmine, haematoxylin, 

 alcohol-cochineal and Biondi-Ehklich's mixture, and in all cases the 

 same result is obtained; namely, this active amoeboid movement or 

 conjugation of nuclei is revealed, usually, though not always, after 

 the animals have been living upon scant supplies of food. 



These facts are probably of some importance in relation to the 

 phenomena of nuclear conjugation as witnessed in the process of the 

 union of the nuclei of sex-cells. At first one would almost be tempted 

 to assert that the amoeboid wandering nuclei were behaving like phago- 

 cytes, but as one nucleus simply fuses with the other, and is not 

 swallowed and assimilated by it, such a view has at once to be given 

 up. In most cases the attraction of the pair of nuclei for each other 

 seems equal and to be reciprocal as in Fig. 2, though nuclei were 

 sometimes seen that were extending a single long pseudopod into an 

 adjacent cell in which the nucleus was quiescent. In this last case 

 the active nucleus might perhaps be compared in a measure, to a 

 spermatozoon, while the quiescent one might be likened to the female 

 or egg-nucleus, but the whole process of conjugation here differs from 

 the sexual in that it is effected by means of nuclear pseudopodia. 



The presence of centrosomes in connection with these phenomena 

 was suspected but they could not be demonstrated. As far as we are 

 aware this is the first recorded instance of the conjugation of the 

 nuclei of the adjacent cells of a physiologically functional epithelium. 

 The cells of this epithelium, moreover, do not lose their cellular 



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