Dec. 25, 1884] 



NA TURE 



171 



1884, we at last get the following remarkable statement : — " The 

 bacilli are not quite rectilinear, like other bacilli, but slightly 

 curved, like a comma. The curvature is sometimes sufficient 

 to give the bacillus a semicircular form" (see woodcut, fig. F). 



I think that it is abundantly clear that the organism selected 

 by Dr. Koch in Egypt as the cause of cholera is not the same 

 organism as that which he selected when in Tndia, and that, 

 although he is aware of that fact, he has not explicitly stated it, 

 but has on the contrary (as d .es the writer in Nature) endea- 

 voured to give the impression that they are the same organism. 



A further point of great importance as affecting the validity 

 of Dr. Koch's theories, with regard to the connection of what 

 he calls the comma-bacillus with cholera, is the statement of Dr. 

 Lewis which is abundantly confirmed, and is not disputed by 

 Koch, viz. that comma-bacilli, indistinguishable in appearance 

 from those occurring in cholera cases, are quite common in the 

 mouths of healthy persons. There is no doubt whatever that 

 this is the c se, although no record of the fact is to be found in 

 any published treatise or paper on Bacteria, and that it was not 

 commonly known to bacteriologists previouly to Dr. Lewi-'- 

 announcement of it in last September. The writer of the 

 article in Nature of December 4 hardly gives full effect to the 

 importance of this point, since he cites Dr. Koch's reply to Dr. 

 Lewis at the same lime that he records Dr. Koch's earlier 

 statements. Setting aside for the moment Dr. Koch's reply to 

 Dr. Lewis, let us examine Dr. Koch's statements bearing on 

 this subject, at the time when he announced his supposed dis- 

 covery of the cause of cholera. He wrote from India that the 

 organisms which he identified as the cause of cholera were of 

 peculiar form, and " on account of its peculiar form, I have given 

 to it the name of comma-bacillus." Throughout his subsequent 

 writings, previous to the publication of Dr. Lewis's report by Uie 

 Army Medical Department, Dr. Koch speaks of his cholera- 

 organism as lie comma-bacillus. He does not mention that 

 any micro-organism similar to it in form is known to him. Had 

 he been acquainted with one c mm inly occurring in the mouth, 

 he would certainly have said, " The cholera comma is very like 

 one occurring in the mouth, but differs in such and such ways." 

 So far from this, he expressly says that no similar organism 

 occurs in the human body, and states that he has failed to find 

 an organism like the comma! acillus in (amongst other places) 

 the human mouth. No subsequent statement (after Lewis's pub- 

 lication) can affect the evidence which we have here that Dr. 

 Koch was not acquainted with the "comma" which occurs in 

 the human mouth. 



After Dr. Lewis had shown that a " comma-bacillus " indis- 

 tinguishable from Koch's "comma-bacillus" occurs in the 

 healthy human mouth, and that accordingly — if we may suppose, 

 from their identity of form and close association, that the two 

 organisms are identical in every respect — the fundamental pro- 

 position of Koch* as to the exclusive association of his comma- 

 bacillus with cholera utterly breaks down, Dr. Koch replied as 

 follows — (1) that the occurrence of a comma-bacillus in the 

 mouth had long been familiar to ! acteriologists (he did not say, 

 it is to be noted, that it had long been familiar to him) ; and (2) 

 that this comma-bacillus of the mouth will not grow upon 

 neutralised cullivating-gelatine, whereas that from the intestine 

 will, and that accordingly there is no ground for regarding 

 them as idenl ical 



It seem- to me in the highest degree improbable that Dr. 

 Kn.li was acquainted with the mouth-comma when he published 

 cause of cholera. If he was acquainted 

 with it, it is undenia le that lie committed a very grave fault in 

 not drawing attention to it, and pointing out then and there the 

 differences presented by cultures of the two commas. 1 have 

 fairly com e before me of the fact that Dr. Koch 



was not acquainted with the comma-bacillus of the mouth two 

 years ago, when he published his large report and coloured 

 I iibercle-bacillus. In one of the drawings in 



■ . a delineation of the chief fornix of micro- 

 ring in the mouth, in order a, he says to enable 

 other observers to guard themselves against any confusion ol 

 the tubercle-bacillus with the microorganisms which are nor- 

 mally present in sputa. No comma-like organism ii figured in 

 that drawing or mentioned by Dr. / 



As to the cultures of the "comma'' from cholera intestines 

 on the one hand, and f ran the healthy mouth on the other, 

 differing i ,"„■ their sensitiveness to 



conditions of alkalinity rality, ] >. say that, 



taking into consideration the whole history of 1 he ease, it is not 



sufficient for Dr. Koch to tell us in an abrupt May that such 

 differences exist. There is no reason to accept as final and 

 perfect Dr. Koch's account of the characters of the comma 

 associated with cholera, and I hould greatly prefer to have the 

 comparison of the conditions of growth of the iomma~ from 

 these two sources made by some one who is not, as Dr. Koch 

 must unfortunately be, so very seriously biased in one directi n. 



I think there is some reason to expect that we shall hear from 

 Dr. Klein as to the result of his i - p rtia] experiments, now- 

 being carried on in Calcufa, that the comma which occurs in 

 the healthy v. outh behaves in precisely the ame way under 

 cultivation, and is in fact as in appearance the same organism s 

 the comma which occurs in the intestines of cholera patients. 



La-tly, I may record a protest against Dr. Koch's ext a 

 o dinary te m "comma-bacillus." 1 have already pointed out 

 that Dr. Koch uses botanical terminology loosely. The word 

 "bacillus" has been by common consent restricted to the de- 

 scription of such rod-like forms as Koch first as ociated w ith 

 cholera as the res.ilt of his Egyptian work. To prefix the word 

 " comma " to this, was perhaps a method of avoiding unpalatable 

 explanations. At the same time it is utterly inconsistent with 'he 

 sense of the words. What Koch calls "comma-bacilli " may for 

 convenience be termed "commas." They are well known to 

 botanists as the segments of a spirillum (see woodcut, fig. e), the 

 result of ilie ! 'leaking up of a spirillum into little pieces, one 

 corresponding to each turn of the spire. They have been clearly 

 figured and their nature recognised by Zopf. The "commas" 

 of tiie human mouth and intestine are undoubtedly related to a 

 spi ilium which is frequently found in association with them, and 

 would no: have caused any astonishment or been stigmatised as 

 "peculiar" in form by an ob erver who had that adequate 

 kn >wleuge of the natural history of the Schizomycete- in 

 general which Dr. Koch h is in many ways shown that he does 

 not possess 



E. Ray I.ankes. f.r 



[We desire merely to make one remark with regard to the 

 foregoing letter. The article referred to was prepared at the 

 request of the Editor with the view of putting before the scien- 

 tific public a fair and complete statement of Dr. Koch's case. 

 The writer of the article requests us to state that he did not, 

 except in the last paragraph, give any views of his own, and holds 

 himself perfectly neutral in the matter, his mind not being at all 

 made up on the subject. — Ed.] 



On the D!s'ritulion of Honey-Glands in Pitchered 

 Insectivorous Plants 



The four genera of pitchered insectivorous plants at present 

 in general cultivation are Nepenthes, Sarracenia, Darlingtonia, 

 and Cephalotus. Attention was drawn to the minute structure 

 and physiological action of the first three of these by Sir J. 

 Hooker in his celebrated presidential address to the British 

 Association in 1S74, while the structure and morphology of the 

 last was treated of by my master, Prof. Dickson (Journal of 

 Botany, 1S78, 1SS1). Both observers pointed out an attractive 

 surface studded with honey-glands, which constituted the lid 

 part, a conducting surface, either of an exceedingly smooth 

 nature (Nepenthes), or beset with small downward-directed 

 hairs (Sarracenia, Darlingtonia, Cephalotus), and in most cases 

 a. glandular surface (Nepenthes, .S. purfmrer, and Cephalotus), 

 the secretion from which directly or indirectly assisted in diges- 

 tion of animal products. In Sarracenia and Darlingtonia 

 there w '- found in addition adelentive su>fac , covered with long 

 deflected hairs. 



A year ago Prof. Dickson further drew attention to a set of 

 magnificent attractive glands along the free edge of the corru- 

 gated rim in Neper .lies, which he named "marginal glands." 



My attention has recently been directed to all the genera, and 

 I propose stating here the main results. A detailed account of 

 the comparative re ults obtained by examination of the different 

 specie^ in the young and adult condition will shortly be presented 

 to the Royal Society of Edinburgh. 



Nepen'hes. — Examining a pitcher of Veitch's beautiful hybrid, 

 N. Mastersiana, I observed on its outer surface what seemed 

 to be the small openings of honey-glands. When microscopically 

 examined, they were found exactly to resemble those on the 

 inner lid surface, except that the gland fossa was deeply hol- 

 lowed out, and opened externally by a small orifice, while its 

 inner surface was clothed to within a short distance of tin irifice 



