226 



NATURE 



[August 17, 191 1 



Guide, we are told that Dolichosaurus was still in exist- 

 ence in the Chalk, whereas it is only known from that 

 formation. 



In part ii. of the Proceedings of the Zoological Society 

 of London, published in June, Dr. W. N, F. Woodland 

 has published a thesis " On the Structure and Function of 

 the Gas Glands and Retia Mirabilia associated with the 

 Gas Bladder of some Teleostean Fishes." The structure 

 of these bodies is well illustrated by eight coloured plates, 

 and an ingenious hypothesis is advanced to explain the 

 remarkable conformation of the well-known rete mirabile 

 duplex constantly associated with the gas gland (oxygen 

 gland). The general theory put forward to explain the 

 actual mode of production of oxygen by the gland — a very 

 interesting physiological problem — is, we notice, almost 

 entirely based upon the study of stained microscopic pi' 

 parations, and thus lacks the essential support only to be 

 derived from physiological experiment. The author, how- 

 ever, has recently investigated the physiological aspect of 

 the subject at Plymouth, and has supplied an account of 

 the i -Mill-- obtained in a further paper to be read before 

 Section I at the forthcoming meeting of the British 

 Association at Portsmouth. 



Prof. Hans Driesch's essay " Die Biologie als selb- 

 standige Grundwissenschaft und das System der Biologie," 

 almost entirely rewritten, has appeared in a second edition 

 (Leipzig: Wilhelm Engelmann, price 1.20 marks). The 

 book is issued as " Ein Beitrag zur Logik der Natur- 

 wissenschaften," and is a clear statement of the value of 

 the interaction of philosophy and biology. 



The new volume (xliii., 1 and 2 Heft) of the Morpholo- 

 gisclies Jahrbuch (Gegenbaur) contains. among othi r 

 memoirs, a detailed account of the spinal cord of the 

 dugong, by Drs. Dexler and Eger. The simple segmenta- 

 tion of the body of the animal and its adaptation to 

 aquatic life are found to be reflected in the cord, which 

 is almost uniformly segmented, and exhibits no trace of 

 thickening in the lumbar region ; there is, however, some 

 shortening in the cervical portion. The form, size, 

 stainability. position, pigment, tigroid substance, nuclei, 

 and processes of the nerve cells do not present any special 

 peculiarities. Dr. Hans Bluntschli describes an abnormal 

 pelvis of a female Java ape [Macacus cynomolgus), which 

 exhibits differences from the normal similar to those shown 

 by a human " Xaegele pelvis." Dr. K. Ogushi contributes 

 the first instalment — the description of the skeleton — of his 

 account of the anatomy of the Japanese three-clawed turtle 

 Trionyx japanicus). 



Prof. Raymond Pearl deals in the current number of 

 Scientia with biomedical ideas in biology, their signifi- 

 cance and limitations. He points out that the real pur- 

 pose of biometry is the general " quantification " of 

 biology, that the biometrical constants (mean, standard 

 deviation, coefficient of correlation, &c.) are constant 

 ■ lers of the " group " (for instance, a species) as 

 such, and that the shape of the variation curve for the 

 particular group of organisms is a definite character for 

 the group. Biometry furnishes, in fact, a valuable and 



1 1 ili' descriptive method; but it must 



not be applied loosely; il 1- necessary to use in its appli- 



1: hi as much general "biological intelligence" in regard 

 to the significance of the problem attacked, the validity of 

 the assumptions made, and the applicability of the methods 

 to the particular problem as would be exercised in an 

 investigation by any other method. 



The second Heft of vol. xcviii. of the Zeitschrift fiii 

 nschaftliche Zoologie comprises three memoirs. Herr 

 NO. 2 l8l, VOL. 8/] 



Rungius gives a detailed account of the anatomy and 

 histolog) ol the alimentary canal, larval and adult, of the 

 water beetle Dytiscus marginalis. Dr. Gustav Fritsch 

 describes the histology of the eye of a fruit bat (Pteropus) 

 from Sumatra. The remarkable point in the structure of 

 the eye is the presence of finger-like processes 1 

 from the choroid into the middle layer of the retina. The 

 author regards these as comparable to the pecten of the 

 eye of birds, and attributes to them a nutritive function 

 and the rile of regulating pressure in the eyeball. Herr 

 Kapzov has investigated the intimate structure of the 

 cuticle of insects, and finds that it has a honeycomb 

 appearance, due partly to variations of pressure during its 

 formation, and partly to varying activity of the hypo- 

 dermis cells which secrete it. 



Among the articles in the July issue of The Po; 

 Science Monthly is one by Mr. A. H. Thayer on conceal- 

 ing coloration, the writing of which was prompted, in the 

 first instance, by certain statements in Mr. R00-' 

 recent book on African animals. Mr. Thayer holds that 

 it is the rule for animals to be coloured like the back- 

 ground which most concerns their feeding and escaping 

 attack ; but the human observer, in order to experience 

 the concealing effect of such marking, must look at the 

 animals from the same level as their normal enemies ; in 

 many cases he must look up to them from near the level 

 of the ground. The reed and sky markings of zebra and 

 oryx make it difficult to distinguish them, in their usual 

 surroundings, by night as well as by day. Prof. Mont- 

 gomery advocates the expansion of the usefulness of 

 natural history museums. lie holds that they should be 

 centres for instruction in taxonomic work, which can be 

 better undertaken there than in university laboratory s. 

 Under such an arrangement, taxonomic collections and 

 courses may well be abolished from universities. He also 

 enters a plea for increased opportunities for researi I 

 lb. si;, Ms of inns, ■uuis. 



The July number of Tropical Life is devoted to an 

 account of the rubber exhibition recently held in London. 

 An important feature was the excellent quality and appear- 

 ance of certain samples of Castilloa, Funtumia, and Ceara 

 rubber. Castilloa rubber from Mexico was shown in 

 block, sheet, and crepe forms ; Funtumia and Ceara were 

 sent from the Gold Coast as " biscuit," as well as in 

 balls. Specimens of Castilloa from Tobago, comparing 

 favourably with sheet Para, received general commenda- 

 tion. 



Noteworthy among the numerous diagnoses of new 

 plants, chiefly from tropical Africa and Asia, published in 

 the Kew Hull tin (No. 6), an- the descriptions of two 

 species of Impatiens from Malaya, communicated by Sir 

 Joseph Hooker; Impatiens peltata is distinguished by its 

 peltate leaf, and /. Vaughanii bears characteristic sepals. 

 Another important determination is supplied by Dr. O. 

 Stapf of a lawn grass, locally termed blue couch, that has 

 found favour in some coastal districts in New South Wales. 

 The author refers it to Digitaria didactyla, specimens of 

 which he has also discovered from Madagascar and 

 Tonkin. It grows more strongly than Cynodon dactylon, 

 which is generally employed for lawns in the colony, and 

 is said to possess other advantages. 



Prominence is accorded to a contribution by the eminent 

 zoologist Prof. E. Giglio-Tos in the Botanisches Central- 

 blatt (July 151. in which it is claimed that the recent 



periments with reciprocal hybrids recorded by Prof. 

 ,1- Vries, and briefly noted in these columns (Nature, 

 April 13), provide striking confirmation of certain laws in 



