336 SCIENCE PROGRESS 



The Pigmentary, Growth and Endocrine Disturbances induced in the Anuran 

 Tadpole by the early Albation of the Pars buccalis of the Hypophysis. 



[Pp. 112, with 19 plates, 10 figures and 1 1 tables.] (American Anatomical 

 Memoirs. Wistar Institute of Anatomy and Biology, Philadelphia. 

 October 1920. Price $3.) 



The animal principally used in these experiments, of which this memoir is an 

 account, was Rana boylei Baird, although Bufo boreas was also so employed. 

 Larva 3 J-4 mm. long proved to be most suitable for the purpose, since at that 

 time the reflex action has not made its appearance and the hypophysea in- 

 growth is fairly readily removed without damage to the brain or other tissues. 

 Both species proved fairly easy to rear under the conditions demanded by the 

 experiment, and could be maintained for relatively long periods of time after 

 operation. This early removal of the epithelial component of the hypophys in- 

 duces disturbances in the pigmentary system, the ratio of growth and alterations 

 in the structures of most other endocrinic organs. The changes in pigmenta- 

 tion result from a diminution in free epidermal pigment, a reduction in number 

 and content of the epidermal melanophores and an expansion of the xantholeu- 

 ■cophores. The result is the production of a silver grey " albino " and the cause 

 of the changes is studied by reciprocal skin exchanges. The neural lobe and 

 pituitary floor appear to be dependent upon the presence of the epithelial 

 hypophyses for their complete development. The thyroid and adrenal cortex 

 are strikingly diminished in size, the adrenal medulla suffers a qualitative 

 change as revealed by staining. It is interesting to find that in cases where 

 the extirpation was incomplete partial albinos were produced, but these did 

 not show such deep-rooted changes in the other endocrine organs. 



The growth of the tadpole after buccal hypophysectomy is retarded 

 slowly at first but increasing to a maximum in the mid -larval period. How- 

 ever, by feeding with fresh anterior lobe of beef pituitary, a practically normal 

 growth rate can be restored and since the animals do not metamorphose they 

 attain an even larger size than normal tadpoles. These growth " maintain- 

 ing " substances cannot be extracted by boiling in water or alcohol, nor does 

 this procedure destroy them since they are left in the residue. 



The paper is printed and illustrated in the excellent manner that is now 

 associated with the publications of the Wistar Institute, and forms a valuable 

 piece of physiological experimentation. C. H. O'D. 



PHYSIOLOGY 



Essentials of Physiology. By F. A. Bainbridge, M.D., D.Sc, F.R.C.P., 

 F.R.S., and J. Acworth Menzies, M.A., M.D. [Pp. iv + 497, with 

 194 illustrations. Fourth edition.] (London : Longmans, Green & 

 Co., 1920. Price 14s. net.) 



This is an unusually excellent little book. It contains in less than 500 pages 

 of clear type, with nearly 200 illustrations, not merely a resume of the main 

 facts of physiology, but, in addition, a connected and reasoned account of 

 the science, with no inconsiderable amount of lucid and concise explanation. 



The illustrations are good as well as numerous ; but mammalian cardiac 

 nerves would be more interesting than those of the frog in fig. 112, and a 

 schema of the lung more helpful than the diagram given on p. 275. 



Judged from the order of presentation of the various systems, the work 

 is intended as an aid to revision rather than as a first book for the beginner. 

 It is particularly well adapted for the former purpose, and we recommend 

 it, cordially, to the student of medicine as a valuable help towards polishing, 

 summarising, and co-ordinating his earher impressions of text-book physiology. 



W. L. S. 



