ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 841 



Preparation of Ova of Ants and Wasps.*— Dr. F, Blochmann ex- 

 amined Cainjponotus ligniperda Latr. and Formica fusca L. The ovaries 

 were usually fixed with picric acid or sublimate, and stained on the slide 

 with picrocarmine or borax-carmine. For examining the elements of the yolk, 

 double staining with borax- or picrocarmine and bleu de Lyon are advised. 

 The prej)arations, not always successful, show in favourable cases a blue 

 staining of the yolk-granules and a rosy colour of the surrounding plasma, 

 sometimes with a tendency to violet. A somewhat similar eifect was 

 obtained by the addition of a little picric acid to the turj)entine oil used 

 for clarifying. The yolk-sac and the chorion are recognizable from the 

 deep blue they acquire from the bleu de Lyon. Young ova of Camponotus 

 ligniperda are noteworthy on account of the rod-like corpuscles containing 

 highly refracting granules, and which after being treated with 1 per cent, 

 acetic acid appear more clearly. The addition of 5 per cent, soda solution 

 to the rodlets causes them to pale in fifteen to thirty minutes, and finally to 

 disappear, while the chromatin masses in the nuclei immediately disappear. 

 Against the bacterial nature of these rodlets is to be said that bacteria from 

 hay-infusion are not altered by immersion for three days in 5 per cent, 

 soda solution. In dilute albumen solution in a moist chamber at 30°, after 

 about twenty-four hours they inflate in places, and finally become quite 

 bladder-like. In trypsin solution they become granular at first, and after- 

 wards are partially dissolved. 



Preparing Ova of Mysis Cliamaeleo.t — Herr J. Nusbaum is of opinion 

 that one method of preservation can never afford satisfactory material for 

 study, as each method gives different results. Thus, in treating fresh ova 

 with Kleinenberg's or Perenyi's fluid we get large and distinct cellular 

 elements, but the yolk is lost very easily ; on the other hand, when the ova 

 are treated for a few seconds with hot water and then with bichromate of 

 potash, the yolk remains with the elements, but the latter contract. After 

 the ova had been from twenty-four to forty-eight hours in a weak solution 

 (1 per cent, of chromic acid or bichromate of potash, or for four to five 

 hours in Kleinenberg's or Perenyi's fluid, they were put into 70 per cent, 

 and then into absolute alcohol. The eggs thus hardened were coloured 

 in toto by haematoxylin, borax-carmine, or red magdala ; the first of these 

 was very useful, because, in the early stages of development it gave a 

 difierent coloration to the not yet modified yolk, and the yolk which was 

 already modified by the influence of immigrated cells. As in all researches 

 on Arthropods, the red magdala gave a perfect staining reagent, as it 

 coloured the eggs and embryos in a relatively short time (a few hours), and 

 very intensely, though sometimes too uniformly. 



The hardened and stained egg was put into alcohol, then into a mixture 

 of equal parts of 70 per cent, alcohol and essence of cloves, and then into 

 pure essence of cloves, until it became transparent ; it was then plunged 

 for a short time into essence of turpentine, and finally imbedded in 

 paraflSn. Sections were made by Schanze's microtome, fixed by collodion 

 and essence of cloves, and put up in Canada balsam. 



Preparation of Male Reproductive Organs of Cypridae.J — Dr. F. 

 Stahlman teases out the fresh animal in physiological salt solution, and 

 stains with picrocarmine, methyl-green, acetic acid, Schneider's acetic 

 carmine. The best fixation is with hot water from 60-65°, or with hot 



» Zeit.schr. f. Wiss. ZooL, xliii. (1886) pp. 537-720 (5 pis. and 6 figs.) 

 t Arch. Zool. Ex per. et Gen., v. (1887) pp. 124-5. 



X Zeitschr. f. Wiss. Mikr., iii. (1886) pp. 511-2. From Zool. Inst, zu Freiburg i. B.. 

 1886, 33 pp. (1 pL). 



