6l6 SUMMARY OF CURRENT RESEARCHES RELATING TO 



10 parts. In this the eggs are left for from 30-60 minutes, and after 

 washing in water are passed through alcohols up to 70 p.c., the excess 

 of sublimate being removed with iodine. 



Sometimes the eggs were next placed in 10 p.c. hypochlorite of 

 sodium or potassium to soften the connective tissue and the egg mem- 

 branes, bat generally the shells were removed with needles after the 

 alcohol stage. 



The younger blastoderms were picked off the yolk and sectioned, but 

 in later stages the eggs were cut whole, and in order to orient whole 

 eggs in paraffin it is necessary to stain them, and best with borax- 

 carmin. The sections were stained with hamialuin or with iron- 

 ha^matoxylin. The former gave by far the better results. 



Studying End-Organs of Rhynchobdellida.* — W. Mayer almost 

 exclusively used Clepsina sezoculata in his research, the exceptions being 

 C. marginata and Pisckola geometra. The material was fixed either in 

 sublimate-acetic acid or in chroni-osmium-acetic acid, and then stained 

 en masse with borax-car inin. Sections from these pieces were after- 

 stained with Blochniann's solution. Other sections from material not 

 treated en masse were stained with iron-hamiatoxylin, van Gieson, 

 hematoxylin and acid fuchsin, and methyl-green. Special methods 

 were also adopted for staining the nerves. For the intra- and supra- 

 vitam methods, methylen-blne J to ip.c. solutions were used, the injected 

 material being afterwards fixed with molybdenate of ammonium and then 

 imbedded in paraffin. Golgi's rapid method was also used. For this 

 the pieces were immersed for 1 or 5 days in potassium bichromate, then 

 followed by f p.c. silver nitrate, and imbedding in celloidin. 



Studying the Vascular Endothelia and Blood of Amphibia.t — 

 Kati Marcinowski fixed the material (embryos of Bufo and Siredon pisci- 

 forme), with a mixture of picric acid and sublimate for from 10-24 

 hours. Af ter washing in water, the objects were dehydrated in up-graded 

 alcohols and then transferred to cedar oil for preservation or direct 

 imbedding in paraffin. The paraffin used was a mixture of hard super- 

 heated I and an ordinary paraffin -§-. The imbedding temperature was 

 kept as low as possible. The sections were mostly stained with borax - 

 carinin. 



Studying the Histogenesis of Cercariaeum helicis.J — 0. F. Roewer 

 fixed the material, kidneys removed from snails, in Rabl's sublimate- 

 platinum-chloride mixture, in hot sublimate or in osmic acid. That 

 fixed with osmic acid was afterwards treated with silver nitrate, while the 

 material fixed in sublimate was stained with borax-carmin (in sections), 

 or with carminate of sodium (in bulk). In the latter case the sections 

 were contrast-stained with indigo-carmin-picric acid, or a mixture of 

 bleu-de-Lyon and ammonium picrate. The formula for the latter is as 

 follows : 25 c.cm. bleu-de-Lyon (1 p.c. in distilled water), 65 c.cm.. 

 ammonium picrate (saturated aqueous), 10 c.cm. picric acid (saturated 



* Zeitschr. wiss. Zool., lxxxi. (1906) pp. 599-631 (3 pis.). 

 t Jeua Zeitschr. Nat., xli. (1906) pp. 19-112 (5 pis.). 

 j Tom. cit., pp. 185-228 (2 pis.). 



