CANALICUI.AK A IT. \KATUS OF ANIMAL CELLS. 185 



cit.) were penetrated by a network derived from surrounding 

 capsul.tr cell-. Holmgren found the nerve cells of Helix pomatia 

 particularly suitable for the demonstration of these intracellular 

 nets of capsular origin. He found here that UK- nerve cells 

 were provided \vith a richer or poorer network of juice-canals, 

 which were formed in the interior of a network of processes 

 derived from other cells. He even found nucleated strands 

 within the bo- lie- of t lie nerve cell. In later publications \ Holm- 

 gren, '01, '02, et< he has developed this hypothesis on tlie ba-i- 

 of results obt. lined by the employment of a new method, lie 

 fixed hi- m.iteri.i! in trichloracetic acid, or trichlorlactic acid, 

 and -lained it v\ith a fre-hly prepared solution of Weigert's 



rcin-fucli-in. H\ this method the protoplasm of the nerve 

 cell- -taiii'-d faintly luit thai of the intracapsular cell- stained 

 dark \iolet. as did al-o the processes of the latter. By this 

 me. in- lie wa- able t., -. r processes of the darkly stained intra- 

 cap-ular ci 11- \\hich penetrated the nerve cells, branched within 

 them, and ana-h >ni"-ed with one another, in order to produce 

 an intracellular uet\\ork. lie applied this observation al-o to 

 the ner\e cell- . s, and came to the conclusion that 



ihe latter were ])-netrat-d by processes of other cells which 

 branched and aiia-iomo-<-d I ret 1\'. to form in the interior <.| the 

 iiti\e cell- a "spongioplasma" which, however, in no wise be- 

 lonvied to the neixetell. but was of extraneous origin. In the 

 interior t the-e mi- juice canals coukl arise, which communi- 



. d directK \\ith -imilar -paces in the interior of the matrix- 

 tell- of thi- iKi. lo ihi- net of cxtraneou- origin Holmgren 

 .e tin- name " t npho-| ...n^ium." He regarded therefore the 

 tro|iho-|>..n-ia not a- tixe.l -tmctures, but as undergoing a om- 

 -tant change, v. hich depended upon the physico-chemical proc- 

 i 5S( - in ih. cell, and thought that, while at one moment the net- 

 work of cell pi might sacrifice itself by liquefaction to 

 the need- of the ner\e cell, it might later be regenerated, by 

 new gro\\t h !' the pro..--- fnun without. He ilm- abandoned 

 com])letel\ hi- t'ornu r view that the canals nprc-cined circu- 

 lator\ or l\'iupliatic -tructures. or a drainage -\-HMII, in la\or 



Foi m] ; l..lingren. E., "Ni - ! ti g< zui 



ili-t /rllr," in "Merkel-Bonnet ! \'"l. ti, p. 



