26 



NA TURE 



[November 14, 1907 



Ihxs, 190,5. Briclly, this concerns an owl which 

 the author then described as a new species — Athene 

 chiaradia ; in the volume now before us it is accorded 

 still the rank of a species. Though it is scarcely to 

 be expected that ornithologists will recognise this bird 

 as entitled to specific rank, the history which Prof. 

 Giglioli gives of its discovery will never lose its 

 interest. 



Within the space at our disposal, it would be im- 

 possible to tell the whole story of this most remark- 

 able case. Suffice it to say that the bird upon which 

 Prof. Giglioli founded his new species was a nestling 

 taken from a nest at Pizzocco, in the province of Udine. 

 Though obviously nearly related to the little owl 

 (Athene noctua), it differed therefrom, among other 

 things, in having a dark brown instead of a golden- 

 yellow iris — a rather remarkable fact. Naturally, 

 the author at once instituted a search for further 

 examples from this neighbourhood, and two years 

 later this search was rewarded by the discovery of a 

 nest — in close proximitj' to that from which the ori- 

 ginal specimen was obtained — containing four 

 nestlings. One of these, be it noted, was a typical 

 Athene chiaradiae, while the remaining nestlings 

 were as typically examples of the little owl {Athene 

 noctiia)l Two other nests contnining both dark and 

 yellow-eyed young were later found, and finally a nest 

 with both types of young, together with the parents, 

 was taken. Though these parents were undoubtedly 

 "little owls," they were both somewhat abnormal 

 specimens, both in the matter of size and color- 

 ation. 



It is to be deplored that no attempt whatever was 

 made to induce any of these birds to breed in con- 

 finement ; or that the parents were not allowed their 

 freedom in the hope that they might at least go on 

 perpetuating these strange aberrations. Instead, 

 every single bird was killed to furnish specimens for 

 the natural history museum at Florence. Thereby 

 some extremely valuable facts were lost to science for 

 ever ! Had Prof. Giglioli endeavoured to breed these 

 birds in confinement, he might have succeeded in 

 establishing his hypothesis of " neogenesis." As it 

 is, both this and the two new species which he founds 

 thereon must be put back to await further evidence. 



Though in some matters we may not agree with 

 Prof. Giglioli, we have said enough, perhaps, to show 

 that his book is by no means a dull catalogue of the 

 birds of Italy. W. P. P. 



PHYSIOLOGY OF ALIMENTATION. 

 The Physiology of Alimentation. By Prof. Martin H. 

 Fischer. Pp. viii+348. (New York: John Wiley 

 and Sons; London : Chapman and Hall, Ltd., 1907.) 

 Price 8s. 6d. net. 



nPHIS is a small but comprehensive account of 

 -I- modern physiological ideas concerning the im- 

 portant subjects of digestion and absorption. The 

 work of physiologists on these questions has of recent 

 years been both laborious and fruitful. Pawlow has 

 devised new methods of examining the secretions and 



NO. 1985, VOL. yy] 



the course of their action on the food-stuffs. The 

 epoch-making work of Emil Fischer has thrown new 

 light on their composition, especiallv in the case of 

 the proteins. The doctrine that enzymes are catalytic 

 agents has taken firm root. The importance of the 

 chemical stimuli to secretion (secretin and other 

 hormones) has been demonstrated by Starling and 

 Bayliss. The sequence of events in the journey along 

 the alimentary tube has been accurately followed by 

 Cannon's shadow photographs. All these points, and 

 many others, are clearly treated by Prof. Martin 

 Fischer in the very useful little book he has pub- 

 lished. 



The introduction of new names for the enzymes so 

 long familiar as pepsin, trypsin, rennet, and the like, 

 will, it is to be feared, introduce confusion to the 

 student's mind, although the new nomenclature aims 

 at uniformity. It is interesting, no doubt, to see the 

 actual shadow photographs which Cannon took, but 

 they do not lend themselves well to reproduction, and 

 more diagrammatic pictures would have been instruc- 

 tive. 



In a few cases the information given is not up-to- 

 date, or is open to question. For instance, Pawlow's 

 results on the stimulation of the nerves of the pancreas 

 require revision in the light of the discovery of secre- 

 tin. These results are given in full, and a few pages 

 later Starling's discovery of the pancreatic hormone 

 is described, but no attempt is made to correlate the 

 two, nor is any guidance given to the reader in 

 estimating their relative value. 



Again, Weinland's ideas on the " adaptation " of 

 the pancreas are quoted with apparent approval, and 

 the confirmation of his views is wrongly attributed to 

 Vernon. No mention, however, is made of the impor- 

 tant work of Plimmer, who has conclusively shown 

 that Weinland's results rest on imperfect methods, and 

 that in the cases investigated no adaptation is dis- 

 coverable. 



The distinction between casein and caseinogen is 

 mentioned, but the former is stated to be produced 

 from the latter by the addition of acid, as well as by 

 the action of caseinase or rennet. This view is justi- 

 fiable if, as some have recently asserted, tlie difference 

 between the two proteins is one of state of aggrega- 

 tion only, and not a true chemical difference. But before 

 adopting such a view it is necessary to dispose of all 

 the work which tends in the opposite direction, and to 

 explain how it is the two substances differ in elemen- 

 tary composition. 



Prof. Fischer assigns the place of protein synthesis 

 in the body mainly to the absorptive epithelium of the 

 intestine, and quotes .^bderhalden as holding the same 

 view. No mention, however, is made of the work 

 of others (e.g. Leathes, Howell, and Schryver), 

 which appears to prove that there is no such special 

 seat of synthesis in the wall of the alimentary tract. 

 There are just a few points where adverse criticism 

 appears to be necessary; there always will be differ- 

 ences of opinion between those who interpret the 

 facts of life. Taken as a whole, the book is not only 

 lucid, but correct and instructive. 



W. D. H. 



