ZOOLOGY AND BOTANY, MICKOSCOPY. ETC. 109 



fly, with especial reference to synapsis, used the larvas of Anax Junius 

 and Plathemis Jydia. Fresh and preserved material was employed. 

 Fresh material was examined in salt solution ; in this condition all the 

 details can be clearly demonstrated, as in the fixed and stained egg- 

 strings. For the finer details, sections were necessary, the material 

 being fixed in Flemming's or Gilson's fluid. The abdomens of the larv^ 

 were opened while submerged in the salt solution ; the ovaries were 

 clipped off with fine scissors, and transferred promptly to the fixative. 

 The stains used were Heidenhain's iron-htematoxylin, Flemming's triple 

 stain, and the borax-carmin-methyl-green method of Obst. 



Demonstrating the Elastic Tissue of the Eye of Birds.* — E. W. 

 Carlier bisected the eyes into anterior and posterior halves, and after 

 removal of lens and vitreous humour the anterior halves were placed in 

 picro-corrosive formalin mixture (Mann). When thoroughly fixed, they 

 were passed through upgraded alcohols, to benzol, benzol and paraffin, 

 and finally pure paraffin. Radial sections, including all the coats of the 

 eye-ball, were then made through the sclero-corneal junction, and after 

 removal of the paraffin were stained with Weigert's elastic stain and 

 mounted in balsam. 



(3) Cutting:, including: Imbedding and Microtomes. 



Photoxylin as an Imbedding Medium. f — Bindo de Vecchi finds 

 that photoxylin dissolved in methylic alcohol forms an excellent im- 

 bedding medium and is superior to celloidin. The procedure is as 

 follows : (1) Immersion of the piece in absolute methylic alcohol for 

 24 hours ; (2) Immersion in 1 p.c. methyHc-photoxylin for from 

 24 hours to several days ; (3) Immersion in 5 p.c. methyHc-photoxylin 

 for similar period ; (4) Exposure under glass bell jar for short time, to 

 allow evaporation of alcohol ; (5) Trimming of the block and fixing to 

 piece of wood with thick gelatin solution ; (6) Exposure to air for 

 about an hour ; (7) Immersion in 85°-90° alcohol until quite hard. 



Sticking Paraffin Sections on the Slide. J — K. Helly disseminates 

 a device which he says never fails to cause the section to adhere by the 

 water method. It consists in passing the perfectly cleaned slide two or 

 three times through the flame from a Bunsen burner just before deposit- 

 ing the section. 



Gelatin-formalin Method of Sticking Microscopic Sections to the 

 Slide. — 01t§ makes his adhesive of 10 grm. gelatin which is dissolved 

 in 100 c.cm. of water. The white of one egg is added to the mixture 

 filtered. To the filtrate 10 c.cm. of 5 p.c. phenol is added. A small 

 piece is liquefied on the blade of a knife and rubbed over the surface of 

 a slide. Celloidin sections are then placed on the slide, and are mopped 

 up and at the same time flattened out by means of blotting paper. A 

 strip of thin paper dipped in 10 p.c. formalin is placed over the section, 

 and another shde on the top. In a few seconds the celloidin sections 



* Proc. Scot. Micr. Soc, iv. (1906) pp. 70-92 (4 pis.). 



t Zeitschr. wiss. Mikrosk., xxiii. (190G) pp. 312-15. J Tom. cit., pp. 330-1. 



§ Tom. cit., pp. 323-8. 



