tiation, it is of much wider interest because in the organisms in question the locahzation 

 of sex organs or cells is linked up with morphogenesis of the body as a whole. This aspect 

 is brought out in all contributions, although in sponges very little is yet known about it. 

 In his 37-page introductory review Vannini sets the stage for the four more speciaUzed 

 papers, one on sponges, one on hydroids and two on planarians. All these are lengthy 

 reviews in English and are illustrated with many hght and electron micrographs. 



IMPLANTATION, PLACENTA, FETAL MEMBRANES AND FLUIDS (see also 47,68) 



Textbooks 



57. 



P. GRUENWALD, ed. 1975. THE PLACENTA and its maternal supply Une: effects of 



insufficiency on the fetus 



MTP, Lancaster. X, 366 pp., 145 figs., 19 tabs., subject index. £ 1 1.50 



This multi-author volume was compiled for use as a textbook, particularly in the 

 relatively recent area of the maternal (non-placental) component of the supply line of the 

 fetus. In his introductory chapter the editor does away with three misconceptions: the 

 idea of the fetus as a successful parasite, the notion of prematurity based on birth weight, 

 and the erroneous concept of placental insufficiency. 



The authors of the volume are 14 American, one West-German, and three British 

 placentologists. More than half of the 19 chapters wUl be of considerable interest to 

 placentologists and mammaUan embryologists. 



The book is well produced and the quahty of reproduction of the photographic 

 illustrations is reasonable. Somewhat strange in a general work of this kind is the fact that 

 the English-speaking authors cite very little recent hterature in other languages. One 

 wonders how much valuable information may be lost in this way. 



58. 



D. H. STEVEN, ed. 1975. COMPARATIVE PLACENTATION, essays in structure and 



function 



Academic Press, London, etc. Monographs for Students of Medicine. XIV, 315 pp., 



132 figs., 5 tabs., subject index. £ 4.80, $ 12.00 (paper) 



Contents: 1. Placenta depicta — illustrations and ideas (Steven), 2. Anatomy of the 

 placental barrier (Steven), 3. Development of the foetal membranes (Steven and 

 Morriss), 4. Placental evolution and embryonic nutrition (Morriss), 5. Placental circula- 

 tion (Carter), 6. Placental exchange of' blood gases (Silver and Steven), 7. Pregnancy 

 and the central nervous system (Priedkalns), 8. Endocrine functions of the placenta 

 (Allen), 9. Placenta as an allograft (Borland), 10. Tumours of the placenta: a break- 

 down in foetal-maternal relationships (Loke) 



This book is intermediate in level between an elementary textbook and a specialised 

 work. It was written by a team of younger British specialists and should be of particular 

 use to advanced preclinical medical and veterinary students. The text is clearly organised, 

 reasonably up to date, and extensively documented. The approach is broadly compara- 

 tive. The book should also be useful to those active in or entering the field of mammalian 

 embryology. 



The book is profusely illustrated with Ught and electron micrographs and very good 

 line drawings, many of which are original. 



96 



