ZOOLOGY AND BOTANY, MICROSCOPY. ETC. 243 



cular parasites was unsuccessful with the blood of Ijirds and fishes. The 

 author notes that in films which dry too quickly the red corpuscules 

 become blistered, a condition which also arises in England if artificial 

 heat be used. 



Fixation of Spirochgeta pallida.* — E. Hoffmann and A. Halle 

 describe an improved method for fixing SpirocJuda pallida, the details of 

 which are as follows : — 5 c.cm. of 1 p.c. osmic acid solution are placed 

 in a watch-glass, and 10 drops of glacial acetic acid added thereto. The 

 watch-glass is placed in a Petri capsule, and clean cover-slips are exposed 

 to the vapour for 2 minutes. Films of the secretion to be examined are 

 then made on these cover-slips in the usual way. The slips are then 

 exposed to the vapour for 1 or 2 minutes. If necessary, the preparation 

 may now be dried in the flame, after which it is placed in a very dilute 

 solution of potassium permanganate for one minute. The film is then 

 washed in water, dried, and stained with Griemsa's solution. The Spiro- 

 chetes are stained red. 



Instead of osmic acid, formalin or pyridin may be used for fixing, 

 but the results are not so good. The authors also mention that fresh, 

 unstained preparations should be used ; the secretion should be mixed 

 with normal saline : this method allows the Spirochetes to be observed 

 alive. 



Studying the Spermatogenesis of Forficula auricularia.f — 

 H. Zweiger collected the material in the neighbourhood of Jena during 

 July and August. The testicles were removed and fixed in strong 

 Flemming for 1 or 2 days, but a mixture consisting of platinum- 

 chloride, chromic and acetic acids, was specially useful for the mitosoma. 

 For staining, Heidenhain's method, safranin and Gram, fuchsin- 

 methylen-blue, and Cajal's methods, were used. 



Studying the Embryo and Larva of Saccocirrus papillocercus.]: 



U. Pierantoni collected the material during the ;-< months of December 

 to February from the sand in the Gulf of Naples. The mature females 

 were first observed under the Microscope, and if full of eggs were placed 

 in little vessels filled with sea-water. The eggs were always laid in the 

 morning, and were at once fertilised by spermatozoa, which escaped from 

 the spermotheca. Another device for obtaining fertilised ova was to 

 rupture a mature female with needles, and so let out the eggs, wliich, as 

 in the natural way, were at once fertilised by the zoosperms which 

 escaped at the same time. 



Live ova were studied in the fresh state by placing them on a slide 

 in sea-water, and supporting the cover-glass by means of minute frag- 

 ments of glass. The fixatives used were Rabl's and Perenyi's fluids ; 

 after half an hour the eggs were transferred to 70 p.c. alcohol for 3 days, 

 and then stained with Delafield's hematoxylin much diluted, or were 

 overstained and afterwards decolorised with hydrochloric-acid alcohol. 

 For sections the same fixatives were used, and also picric acid sublimate. 

 The material was stained in toto with Mayer's hemulum or haemacalcium. 



* Miinchener Med. Wochenscbr, July 31, 1906. See also Brit. Med. Journ., 

 1907, i. Epit. 62. t Jen. Zeitschr. Natur., xlii. (1906) pp. 143-72. 



X Mitt. Zool. Stat, zu Neapel, xviii. (1906) pp. 47-50. 



R 2 



