474 C. CLIFFORD 1)()]!ELL. 



It remaius now to consider how fav these facts coincide 

 with those recorded by others. 



First of all, I would point out that my results are in agree- 

 ment with those of Schaudinn (1902, 1903) and Guilliernioad 

 (1908) — both of whom made accurate cytological investiga- 

 tions of different organisms. Both these observers, however, 

 examined Bacteria which possess a nucleus of the chromidial 

 form : it is with my chromidial forms, therefore, that their 

 results must be compared. Both Schaudinn and (luiniermond 

 — though on different grounds — arrived at an interpretation 

 similar to my own. 



Quite recently, Guilliermond (1909) has recorded the exis- 

 tence of two species ot Bacillus and a S pirillum which 

 possess nuclear filaments like those which 1 have described in 

 tiiese forms. His observations appear to have been made 

 quite independently of mine, and may therefore be taken as 

 confirmatory. 



I find it difficult to decide how fn,r tlio i-esults of Swellen- 

 grebel (1906, 1907, 1907a, 1909, 1909a) coincide with mine. 

 He finds in Bacilli and Spirilla remarkable filamentar 

 structures, usually in the form of an irregular or broken 

 spiral. On account of the micro-chemical and staining 

 reactions of these structures, he is led to interpret them as 

 nuclei. They are not exactly like the filamentar structures 

 which occur in Bacilli of the spi rogy ra type. In many 

 cases they resemble certain of the nuclear modifications of B. 

 saccobranch i. It seems to me possible that in some cases 

 also the a])pea,riuices are the result, of imperfect fixation^ — the 

 orio-inal spiral filament having been broken up in this process. 

 Son)etimes, also, the filaments may be really chromatin 



could confirm my statements as to the existence of the structures wliich 

 I have described — if tlieh- existence were called in question. Among- 

 tliose to whom I have sliown one or other of my preparations may be 

 mentioned Sir Ray Lanlvester. Prof. Adam Sedgwick. Prof. J. B. 

 Farmer, and Prof. F. Yejdovsky — all of wliom liave agreed with me 

 as to the appearances presented. 

 ^ See footnote on p. 417. 



