2 2 



NATURE 



[May I, 18-90. 



particular ammoniacal solution by means of a small quantity of 

 garden soil, was carried on through twenty-four generations, a 

 minute quantity on the point of a sterilized needle being intro- 

 duced from one nitrifying solution to the other. From several 

 of these generations, gelatine plates were poured, and the resulting 

 colonies inoculated into identical ammoniacal solutions, to see if 

 nitrification would ensue ; but, although these experiments were 

 repeated many times, on no occasion were they successful. 



It appeared, therefore, that the nitrifying organism either re- 

 fused to grow in gelatine, or that the authors had failed to find 

 it, or that, growing in gelatine, it refused to nitrify after being 

 passed through this medium. 



Experiments were, therefore, commenced to endeavour to iso- 

 late the organ'sm by the dilution method. For this purpose a 

 number of series of dilutions were made by the addition to 

 sterilized distilled water of a very small quantity of an ammonia- 

 cal solution which had nitrified. It was hoped that the attenua- 

 tion would be so perfect that ultimately the nitrifying organism 

 alone would be introduced. 



After a very large number of experiments had been made in 

 this direction, the authors at length succeeded in obtaining an 

 attenuation consisting of about luo J^nrTr "f the original nitrifying 

 solution employed, which not only nitrified, but on inoculation 

 into gelatine-peptone refused to grow, and was seen under the 

 microscope to consist of numerous characteristic bacilli hardly 

 longer than broad, which may be described as bacillo-cocci. 



Although this bacillo coccus obstinately refuses to grow in 

 gelatine' when inoculated from these dilute media, yet in broth it 

 produces a very characteristic though slow growth. 



Nitrification was also induced in ammoniacal solutions by in- 

 oculating from such broth cultivations. 



March 27. — "On the Progressive Paralysis of the Different 

 Classes of Nerve-cells in the Superior Cervical Ganglion." By 

 J, N. Langley, F.R.S., and W. L. Dickinson. 



Summary. — Generally speaking, stimulation of the cervical 

 sympathetic in the dog with minimal effective shocks causes 

 pallor in the lips and gums ; with weak to moderately strong 

 shocks, primary pallor followed by flushing; with strong shocks, 

 as shown by Dastre and Morat, primaiy flushing, but the extent 

 and duration of the primary effect and of the secondary effect, 

 if there is any, vary in different dogs. 



In the rabbit and cat, stimulation of the cervical sympathetic 

 always causes, as shown by Bochefontaine and Vulpian, primary 

 pallor in the lips and gums, and the after-flush is not great. 

 The pallor we find is bilateral ; the degree of the pallor on the 

 opposite side to that stimulated varies in individual cases, it 

 can be seen in the tongue, as well as in the lips and gums. 



On injecting nicotin into a vein, certain of the normally 

 -occurring effects of stimulating the cervical sympathetic cease 

 before the others, i.e. since all the effects can still be produced 

 by stimulating the fibres running from the superior cervical 

 ganglion, the nerve-cells in the ganglion, which are connected 

 with different classes of nerve-fibres, are paralyzed with 

 different degrees of ease by nicotin. 



Arranging the various effects in the order of ease of paralysis, 

 Ave have : — 



Rabbit. 



(i) Withdrawal of the nictitating membrane. 



(2) Opening of eye. 

 \ (3) Dilation of pupil. 



\ (4) Constriction of blood-vessels of ponjunctiva. 

 /(S) Constriction of blood-vessels of lips and gums. 

 \ (6) Constriction of blood-vessels of ear. 



In one or two cases, no difference in the ease of paralysis 

 between the bracketed actions has been observed. 



Cat. 

 (i) Secretion from sub-maxillary gland. 



!(2) Opening of eye. 

 (3) Dilation of pupil. 

 (4) Constriction of blood-vessels of conjunctiva. 

 (5) Constriction of blood-vessels of mouth. 

 J IS I (6) Constriction of blood-vessels of ear. 

 t (7) Withdrawal of nictitating membrane. 

 {a) Constant differences between these have not been 

 observed. 



(b) These have not been directly compared, but in separate 

 ■experiments each has been obtained when (i) to (5) were no 

 longer seen. 



(i) Dilation of arteries of bucco-facial region. 



(2) Movements of eye and opening of eyelids, 



(3) Withdrawal of nictitating membrane. 

 {4) Constriction of the arteries of gums and lips. 



/ \ ; (5) Dilation of pupil. 



^ ' (6) Secretion from sub-maxillary gland. 



(7) Constriction of blood-vessels of the sub-maxillary 

 gland. 



(a) Differences between these have not always been observed- 



At a certain stage of nicotin poisoning, when stimulation of 

 the sympathetic does not cause withdrawal of the nictitating 

 membrane, but does cause dilation of the pupil, a partial 

 closing of the eye is obtained by stimulating the sympathetic. 



It will be noticed that in each animal nicotin abolishes most 

 of the effects of stimulating the cervical sympathetic at very 

 nearly the same lime. With regard to these, we think that 

 there is only z-primd facie case for regarding the differences ob- 

 served as due to an unequal paralysis of the nerve-cells of the 

 superior cervical ganglion, for it is possible that the differences 

 may be due to an unequal tonic stimulation reaching the parts 

 by nerve-fibres other than the sympathetic. But the greater 

 differences observed, for instance, between the secretion of saliva 

 and the dilation of the pupil in the cat, the flushing of the lips 

 and the constrictioh of. the vessels of the sub-maxillary gland in 

 the dog, we do not think can be due to such a cause, and we 

 attribute them to an unequal paralyzing action pf nicotin upon 

 the nerve-cells of the superior cervical ganglion. 



Linn can Society, April 17.— Mr. Carruthers, F.R.S., Presi- 

 dent, in the chair. — Lord Arthur Russell, on behalf of the sub-- 

 scribers to a portrait of Sir Joseph Dalton Hooker, which had 

 been painted at their request by Mr. Hubert Herkomer, R.A., 

 formally presented the portrait to the Society, and in a few words 

 expressed the satisfaction which he was sure would be felt at the 

 acquisition of the likeness of so distinguished a botanist. It was 

 announced that a photogravure of the portrait was in preparation, 

 of which a copy would be presented when ready to every sub- 

 scriber to the portrait fund. — Prof. P. M. Duncan, F. R.S., 

 exhibited a vertical section through a large coral, Fungia echinata, 

 cutting through and across the septa and synapticulae and the 

 so-called base. The union of the sides of contiguous septa at 

 the base is either incomplete or by means of synapticulse. — Dr. 

 Edward Fischer, of Zurich, exhibited and made remarks on certain 

 species of Polyporus bearing a sclerotium possessing the structure 

 of Pachynia cocos, but it was doubtful whether the Polyporus 

 represented the fructification of the Pachytna, or was merely 

 parasitic on it. Mr. George Murray expressed himself in favour 

 of the latter view. — Mr. J. E. Harting exhibited alive a so- 

 called "singing mouse " which had been captured at Maidenhead 

 a week previously, and which uttered sounds like the subdued 

 warbling of a linnet. He desired to be informed whether the 

 cause usually assigned for the phenomenon was correct — namely, 

 some obstruction or malformation of the trachea. Prof. Stewart 

 stated that he had observed alive, and dissected when dead, a 

 similar specimen, and had found no trace of any organic disease 

 or malformation. — Sir Charles Sawle, Bart., exhibited a specimen 

 of the Little Green Heron, Butorides virescens, of North America, 

 which had been shot by his keeper at Penrice, St. Austell, 

 Cornwall, in October last, and which he had sent for preserva- 

 tion to a taxidermist at Bath. Mr. J. E. Harting offered some 

 remarks on the occurrence, and suggested various ways in which, 

 the bird might have reached England. He observed that the 

 larger American Bittern, Botaurus lentiginosus, had been met 

 with some five-and- twenty or thirty times in the British Islands, 

 and, strange to say, had been described and named by an, 

 English naturalist, and a Fellow of this Society, Colonel George 

 Montagu (who obtained a specimen of the bird in Dorsetshire), 

 a year before it was described by Wilson as a native of the 

 United States. — A paper was then read by Mr. Spencer Moore, 

 on some micro-chemical reactions of tannin. In this an account 

 was given of the behaviour of Nessler's test for ammonia upon 

 tannin, which it usually colours almost immediately some shade 

 of brown or reddish brown. The great value of the reagent is 

 held to reside in the rapidity of its action ; moreover in none of 

 the many experiments did it fail. Reference was also made to 

 some other new tannin tests, especially to some in which, as in 

 Nessler's fluid, caustic potash furnishes the basis, and which, 

 like that fluid, are very rapid in their action.— A paper by Mr. 



