2 THE EMBRYOLOGY OF THE HONEY BEE 



paraffin. By the application of this method Kowalevski was able 

 greatly to extend the boundaries of the knowledge relating to the 

 development of insects, and his memoir may be said to inaugu- 

 rate the period of modern research in this field. In the part 

 relating to the arthropods are included nine pages devoted to the 

 development of the honey bee, illustrated by thirty figures cover- 

 ing plate XI and a half of plate XII. Although that part of the 

 section devoted to the honey bee, which records observations on 

 the living egg, covers much the same ground as that covered by 

 Biitschli in the previous year, nevertheless by the study of sec- 

 tions Kowalevski was able to add many important facts regard- 

 ing the formation of the blastoderm, the origin and fate of the 

 germ layers, and the development of the nervous system. The 

 figures are excellent, and although small, are sharp and clear, 

 while the text is written in a condensed but lucid style. 



Owing probably to the excellence of the observations just de- 

 scribed, over ten years elapsed before the egg of the honey bee 

 was again made the subject of scientific investigation. In 1884 

 a paper by the Italian zoologist Battista Grassi appeared in a 

 relatively obscure journal — Atti dell' Academie Gioenia di scienzi 

 naturali in Catania — , and according to Carriere (1897) re- 

 mained for a time almost unnoticed. This paper covers seventy- 

 seven pages of text (4^0), and is illustrated by 252 figures cover- 

 ing ten plates. This is the fullest, and in fact the only complete 

 account of the embryology of the honey bee ever published. Like 

 his predecessors Grassi studied the living bee, but he also made 

 free use of microtome sections. The text consists of an intro- 

 duction including a brief review of literature, twelve numbered 

 chapters, each descriptive of the development of a tissue or sys- 

 tem of organs, and in addition a chapter discussing the signifi- 

 cance of the facts recorded. This most excellent paper is scarcely 

 open to criticism, when judged by the standard of contempo- 

 raneous papers, and allowing for the relative crudity of the 

 histological technique of that time. Indeed the correctness of 

 most of the facts recorded are beyond question. Nevertheless, 

 judged by modern standards, the text seems lacking in complete- 

 ness, while most of the figures appear crude and diagrammatic, 

 many of them losing much of their value by their small size. 

 In addition the correctness of some of Grassi's statements are 

 open to question. 



