276 



NATURE 



{July 19, 1888 



situated in the tissue of the stem, probably the soft bast. 

 In most other cases it seems to be attached somehow to 

 the reproductive parts of the plant. The quantity that 

 can be extracted from Clematis is, however, much less 

 than from the other plants spoken of. 



The ferment has also been found in the petals of the 

 artichoke (Cynara Scolymus). 



An account of the occurrence of this vegetable rennet 

 would not be complete without its including the re- 

 searches of Dr. Sheridan Lea on Withania coagulans 

 (Proceedings of the Royal Society, 1883). These have, 

 besides their scientific value, a direct bearing upon 

 the commercial aspect of the question. Many of the 

 natives of India refuse to have anything to do with cheese 

 prepared by means of animal rennet, and there is conse- 

 quently there a large field for the employment of the 

 plant. Some years ago Surgeon-Major Aitchison sent 

 home an account of the peculiar property of the Withania. 

 The shrub grows freely in Afghanistan and Northern 

 India, and the natives there have for a long time em- 

 ployed an aqueous extract of the capsules to curdle their 

 milk. Some dried material sent from thence to Kew was 

 used by Dr. Lea in his investigations. Withania is a 

 genus of the order Solanaceae, and has a capsular fruit, 

 containing a large number of small seeds. In the dried 

 material these seeds were enveloped in a coating of a 

 peculiar resinous matter, which was probably the dried 

 juice of the capsules in which they had ripened. The 

 ferment was found to exist to a very slight amount in the 

 stalks of the fruits, and to be extremely abundant in the 

 seeds. From the ground seeds it could be extracted 

 easily by maceration with solution of common salt and by 

 treatment with glycerine. So extracted, it was found to 

 be destroyed on boiling, but to be able to withstand 

 moderately prolonged exposure to alcohol. Its activity 

 in a fairly strong extract was quite equal to that of most 

 commercial samples of rennet prepared from the stomach. 

 It could, moreover, be kept with as great security as the 

 latter by the aid of common salt and a little alcohol. 

 Its commercial value is somewhat interfered with by 

 the presence in the seeds, and in their extracts, of a 

 peculiar yellowish-brown colouring-matter, which cannot 

 be separated without destroying the rennet. 



Since the publication of Dr. Lea's researches the writer 

 has met with the ferment in the unripe seeds of Datura 

 Stramonium, a plant belonging to the same order, 

 Solanaceae. In this plant, though present in the unripe 

 seeds, it appears to be absent from them when ripe. Its 

 exact distribution is, however, not yet determined. 



The occurrence of this property in so many plants, and 

 these not at all closely connected in other ways, leads to 

 the consideration of what must be its physiological signi- 

 ficance. It is perhaps not difficult to see why rennet 

 should occur in the stomachs of young animals whose 

 food consists chiefly of milk, bjt its importance in the 

 vegetable kingdom must be independent of such a 

 function. Further researches, still in progress, may per- 

 haps throw some light upon this point. It is significant 

 so far to notice that its occurrence is mainly in those 

 parts which are especially connected with the reproduc- 

 tion of the plant, a fact which seems to point to a pos- 

 sible function in connection with the storage of proteid 

 food materials for the nutrition of the embryo during 

 germination. J. R. Green. 



THE METEORIC SEASON. 



\ \ J"E have now arrived at a period of the year which is 

 * * full of interest to meteoric observers. The number 

 of meteors visible has greatly increased, as compared with 

 preceding months, and apart from this, observations may- 

 be pursued without the discomfort and inconvenience so 

 often experienced on the cold starlight nights of autumn 



and winter. The impending return of two rich showers 

 is an additional incentive to those who may con- 

 template giving a little time to this interesting branch 

 of astronomy. 



From observations at Bristol on the nights of July 8, 

 1 1, and 12 last, it appears certain that the Perseids (which 

 attain a maximum on August 10, when the radiant is at 

 45° + ST) had already commenced. On July 8 twenty- 

 five meteors were counted between nh. and 13b.. 30m., 

 and these included six paths which denoted a well-defined 

 radiant at the point 3 + 49°, a little south of Cassiopeia's 

 Chair. The visible traits of the individual meteors traced 

 from this radiant were identical with those exhibited by 

 the Perseids which are displayed in August, and the fact 

 that this radiant seen on July 8 is far west of the radiant 

 usually remarked on August 10, does not negative the 

 presumed identity of the two showers. The Perseid 

 radiant which endures a considerable time, changes its 

 position amongst the stars from night to night, and the 

 extent and direction of this displacement will be seen by 

 a reference • to Nature vol. xxxvi. p. 407, where I have 

 described a number of observations secured at this 

 station in July and August of last year. 



When the moon leaves the evening sky towards the 

 close of the present month, observers should watch 

 for the reappearance of the Aquarids which are usually 

 seen in marked abundance about July 27, 28, and 29. 

 The radiant is near h Aquarii, and the meteors are rather 

 slow, usually ascending from low in the south-east, and 

 the brighter ones throw off trains of sparks. Early 

 Perseids are also numerous at the end of July, and the 

 radiant is then closely south of the well-known star 

 cluster x Persei. Observers should register the paths of 

 the meteors and determine the precise place of the 

 radiant on each night of observation. 



Bristol, July 13. W. F. Denning. 



NOTES. 



The proposal that a Professorship for the exposition of the 

 Darwinian theory should be established in connection with the 

 Sorbonne has received the sanction of the Sorbonne authorities. 

 Three members of the Committee by which the matter was 

 decided were opposed to the scheme, but they did not vote 

 against it. They simply refrained from voting. The Sorbonne 

 has asked that the name of the proposed chair shall be changed. 

 One or other of the three words, " evolution," " morphology," 

 "phylogeny," is to be substituted for "philosophy." 



The Birmingham meeting of the Photographic Convention of 

 the United Kingdom will be held from the 23rd to the 28th of 

 July. A programme of excursions and local arrangements has 

 been issued. The Convention will be opened on the evening of 

 the 23rd inst., by the Mayor of Birmingham, at a conversazione 

 to be held in the Masonic Hall in connection with an exhibition 

 of photographs and photo apparatus. 



On Thursday, the 12th inst., the anniversary meeting of the 

 Sanitary Institution of Great Britain was held in the theatre of 

 the Koyal Institution. The Chairman, Mr. Edwin Chad wick, 

 in opening the proceedings, claimed credit for the Sanitary 

 Institution of Great Britain and like institutions for a large pro- 

 portion of the reduced death-rate of the metropolis, which was 

 now 14 in iooo. London in that respect compared very 

 favourably with other places, the death-rate in Paris being 27, 

 Vienna 30, and St. Petersburg 40. The medals and certificates 

 awarded to the exhibitors at the Sanitary Exhibition held at 

 Bolton in 1887 having been distributed by Mr. Chadwick, Dr. 

 B. W. Richardson delivered an address on "The Storage of 

 Life as a Sanitary Study." He began by referring to instances 

 of long life in lower animals and in man. These, he said, by 



