August 28, 1913] 



NATURE 



671 



The histology of this class is usually treated somewhat 

 cursorily in our text-books, mainly because of the 

 minute size of the avine cells in comparison with those 

 of other vertebrates. A number of good text-figures 

 and a plate illustrate the details, most of which natur- 

 ally can interest the specialist only, but there are also 

 observations and conclusions, for instance, those con- 

 cerning leucocytes and the protoplasmic rods of the 

 cylindrical epithelial cells, which are of general physio- 

 logical importance. 



To The Field of August 23 Mr. R. I. Pocock con- 

 tributes an article on the skin-glands of shrew-mice, 

 in which it is pointed out that the gland on the flanks 

 of the British species, which is generally supposed to 

 emit the musky odour characteristic of these animals, 

 is present only in the males. On the other hand, it is 

 developed in both sexes of the Indian musk-shrew 

 (Crocidura), as well apparently as in the Continental 

 representative of that genus. It has been generally 

 stated that the musky odour of all shrews is protective, 

 but, in the member-; of the typical genus, if 

 it be emitted by the gland, it must be a sexual 

 feature, probably designed to attract the females. 

 Before this can be definitely decided, it has to be ascer- 

 tained whether the females of British shrew-mice are 

 musky. If they are not, the numerous shrew-mice 

 left dead by cats in gardens in autumn must probably 

 all be males. Quite apart from the question whether 

 the glands be its source, it seems, on the other hand, 

 quite evident that in the Indian musk-shrew and its 

 near relatives the musky odour is highly protective, 

 rendering these animals obtrusive and " self-advertis- 

 ing." 



The current number of The Quarterly journal of 

 Microscopical Science (vol. lix., part 2) contains a 

 very interesting article by Mr. E. S. Goodrich on 

 metameric segmentation and homology. He discusses 

 the well-known difficulty that organs which are un- 

 doubtedly homologous, inasmuch as they can be'traced 

 back to corresponding parts in a common ancestor, 

 may nevertheless occur on different segments in 

 different representatives of a group. The paired limbs 

 of vertebrates are cited as typical illustrations of the 

 problem. These shift backwards or forwards during 

 the course of evolution in the most perplexing manner. 

 Mr. Goodrich holds that, in order that they may be 

 regarded as strictly homologous, it is not necessary 

 that organs should be developed on corresponding 

 segments in different types, and he accounts for their 

 variation in position by a process of "transposition," 

 rejecting the theories of intercalation and excalation of 

 segments, re-division of the body and migration of 

 the organs in question. 



The August number of The Museums' Journal is 

 chieflv devoted to reports of the recent conference of the 

 Museums' Association at Hull, including the presi- 

 dential address delivered by Mr. E. Howarth. It is 

 illustrated with a portrait of the president, and a 

 photograph of the members of the association at 

 Burton Constable, the seat of Major Chichester- 

 Constable. 



In the second volume 0.1 insects in The Cambridge 

 iSatural History it is stated that the family Fulgoridas 

 NO. 2287, VOL. 91] 



"includes the so-called lantern-flies, in which the front 

 of the head forms a huge proboscis that was formerly 

 believed to be luminous." In the August number of 

 The Zoologist Mr. II. W. Bell-Marley records the 

 emission of light by the adult of a Natal species 

 (Rhinorthra guttata), as well as by parasitic lepi- 

 dopterous larvae with which it is infested. 



The Scientific American announces an alteration in 

 the system of issue of publications by the United States 

 Department of Agriculture. The old independent 

 series of bulletins and circulars of the thirteen pub- 

 lishing bureaus, divisions, and offices of the depart- 

 ment have been discontinued and will be superseded 

 by a new Journal of Research for printing scientific 

 and technical matter, and by a departmental series of 

 bulletins, written in popular language for selected and 

 general distribution. By this plan the confusion that 

 has resulted from the multiplicity of series of public a- 

 tions will be avoided, and the saving of a considerable 

 sum will annually be effected. Under the new plan 

 the department will discontinue the general distribu- 

 tion of matter so scientific or technical as to be of 

 little or no use to the lay reader. It will supply tech- 

 nical information only to those directly interested and 

 capable of using scientific analyses, and of under- 

 standing the results of research work couched in 

 si ientific terms. A larger amount of information in 

 popular form which the average reader can imme- 

 diatelv apply to his own direct advantage will here- 

 after be distributed. 



We have received from Dr. J. H. Maiden a reprint 

 of the presidential address delivered by him last year 

 to the Royal Society of New South Wales. This 

 address ranges over a wide and varied field, and 

 contains much that is of general interest, including 

 obituary notices and memoirs of Sir Joseph Hooker, 

 Lord Lister, and Baron von Mueller. Reference is 

 made to the forthcoming Melbourne meeting of the 

 British Association and to other scientific matters of 

 Australian interest, such as the Northern Territory 

 Expedition of rgn, the exploration of Antarctica, the 

 centenary of the Sydney Botanic Gardens, &c. 

 After dealing with some botanical matters, such 

 as the teaching of botany, a plea for a botanical 

 survey and a new census of New South Wales plants, 

 Dr. Maiden proceeds to set forth in some detail his 

 views regarding the functions of a botanic garden, 

 with suggestions as to work in phyto-chemistry and 

 other practical proposals for increasing the usefulness 

 of botanic gardens in Australia or elsewhere. 



Dr. W. A. Cannon, of the Carnegie Institution 

 Desert Laboratory, Tucson, Arizona, has forwarded a 

 reprint of an interesting paper on some features of 

 the root systems of desert plants (Popular Science 

 Monthly, vol. Ixxxi). Among desert shrubs there are 

 three main types of root system : (1) the superficial 

 type, in which the roots extend horizontally from t Im- 

 plant axis, and lie near the soil surface ; (2) the tap 

 root, which goes directly down to a depth determined 

 partly by the character of the soil, partly by the pene- 

 tration of the rains' and partly by the character of the 

 root itself; (3) the generalised type of root, which not 

 onlv reaches widely, but also penetrates fairly deeply. 



