No. 2.] BA TRA CHOSEPS A TTENUA TUS. 113 



If we turn to the nucleus, we find similarly that the chro- 

 momeres, the chromosomes, and the leaders are also ephemeral 

 and secondary structures which form and disperse, the chromi- 

 oles alone being the permanent individualities of the chromo- 

 somic structures. The nucleus then contains the following 

 permanent granula : linosomes, the chromoplasmic granula, 

 the chromioles, and the granula composing the chromoplasts. 

 The permanent structures of the cell are the centrioles, the 

 chromioles, and the chromoplasts. As regards the primary 

 parts of these last-mentioned structures we are yet in doubt, 

 but there is every reason to believe that these structures are 

 of a highly complicated nature. 



Similarly the fibrillar and alveolar structures of the proto- 

 plasm are only secondary, ephemeral, and temporary. With 

 proper optical means we see that the alveole, as well as the 

 reticulum, is built up of granules. These granules adhere to 

 each other by means of minute projections or arms, for which 

 I have proposed the name of Linopodia. The ultimate visible 

 structure of the protoplasm is thus a granule, capable of pro- 

 jecting and retracting Linopodia. 



For a fuller explanation and demonstration of these facts I 

 must refer to the larger paper now in the hands of the pub- 

 lisher of the Journal of Morphology. 



BIOLOGICAL LABORATORY, 



CALIFORNIA ACADEMY OF SCIENCES, 



SAN FRANCISCO, CALIFORNIA. 



ERRATUM. 



In No. i, p. i, 1 3th line, last word, rend ganglion in place of 

 "gland." 



