ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 



257 



studying the phenomena of fertilisation, a more rapid procedure was 

 adopted. In this the alum mordant was used for 15 to 30 minutes ; this 

 was followed by hematoxylin staining for 1 to 3 hours. Differentiation 

 was effected with great care and constant inspection under the Micro- 

 scope. 



Congo-red was used in contrast stain and gave excellent results. 



Device for Protecting Mounted Sections during Dehydrations- 

 It is a common experience that when a number of slides bearing sections 

 are put in a flask of alcohol, or other fluid, specimens may be spoilt by 

 movements of the slides against each other. C. Funck suggests a 

 simple plan for remedying this (fig. 45). A grid, preferably of nickel- 

 plated brass, of the form shown in the figure, is placed inside the flask, 

 resting on the bottom. The lower ends of the slides rest in the 



Fig. 45. 



numbered spaces. The slides thus remain, touching only at the top 

 edges. The portion of the slide which bears the section is kept free 

 from all contact with its neighbours. 



Injection Methods applied to certain Mollusca. f — B. Mozejko 

 describes a method of gelatin injection for the anatomical investigation 

 of Anodon, Mytilus edulis, and some other Mollusca. For the greater 

 part of his work, the author used a 4-6 p.c. solution of gelatin. By 

 the use of finely pow r dered insoluble mineral dyes, he was able to tint the 

 gelatin variously, and thus differentiate the separate systems or vessels 

 injected. For example, in the case of Anodon, it is possible to inject the 

 arteries, veins, intestine, genital ducts, and the cavities of the organs of 

 Bojanus separately, and thus get a specimen injected in five colours. 

 Specimens so injected can be fixed in formalin, and imbedded in paraffin 

 for the purpose of cutting sections. 



* La Cellule, xxv. (1909) pp. 415-60 (1 pi. and 54 figs). 

 t Zeitsehr. wiss. Mikrosk., xxvi. (1909) pp. 353-77. 



