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SUMMAEY 



OF CUKEENT RESEARCHES RELATING TO 



ZOOLOGY AND BOTANY 



(^principally Invertebrafa and Cryptogamia), 



MICROSCOPY, &c., 



INCLUDING ORIGINAL COMMUNICATIONS FROM FELLOWS AND OTHERS. 



ZOOLOGY. 

 A. VERTEBRATA :— Embryology, Histology, and General. 



a. Embryology, t 



Physics of the Yolk.f — Dr. H. Virchow reports the results of an 

 inquiry (prompted by the observations of G. Quincke) into the physical 

 conditions which lie behind the microscopic phenomena to be seen in 

 studying the yolk of a fowl's egg. Two questions in particular are 

 raised : in what form is the fatty body inclosed in the yolk-spherules, 

 and in what degree do reagents produce artificial features. Herr Virchow 

 describes the phenomena observed in yolk after retention in alcohol 

 for twenty-four hours, after boiling fov half an hour, after treatment for 

 twenty-four hours with concentrated sublimate solution. He gives what 

 seems to be the explanation of some of the differences observable. As 

 to the form the fatty body takes in the spherules, he is uncertain. It 

 is contained, at any rate, in all parts of the spherule, perhaps in the 

 form of fine drops, perhaps in solution in the albumin-body which gives 

 shape to the spherules. 



Embryonic Axis.§— Dr. W. Eoux replies to certain criticisms made 

 by Herr O. Schultze on his researches in regard to the axes of frog-eggs 

 and embryos. On most points of importance the two investigators differ, 

 indeed directly contradict one another. In the present paper Eoux 

 examines the evidence for Schultze's conclusions, and maintains the 

 integrity of his own. 



Spermatogenesis of Vertebrates. |1 — Sig. F. Sanfelice gives a com- 

 pleted account of his researches on the spermatogenesis of Vertebrates 



* The Society are not intended to be denoted by the editorial " we," and they do 

 not hold themselves responsible for tlie views of the authors of the papers noted, 

 nor for any claim to novelty or otherwise made by them. The object of this part of 

 the Journal is to present a summary of the papers as actually published, and to 

 describe and illustrate Instruments, Apparatus, &c., which are either new or have 

 not been previously described in this country. 



t This section includes not only papers relating to Embryology properly so called, 

 but also those dealing with Evolution, Development, and Reproduction, and allied 

 subjects. t SB. Akad. Wiss. Berlin, xxxvii. (1888) pp. 977-81. 



§ Biol. Centralbl., viii. (1888) pp. 399-413. 



II Boll. Soc. Nat. Napoli, i. (1887) pp. 33-45 ; ii. (1888) pp. 42-98 (3 pis.). 



