CYTOPLASMIC INCLUSIONS OF THE GERM-CELLS 273 
Papanicolaou Suggested English 
and Stockard. Older Authors. Equivalent. 
Idiocalyptosome. Periphere Zone des Spitzen- Outer zone of acro- 
knopfs (Meves). Ausserer Teil some (0zA). 
des Mitosomes (Niessing). 
Idiocryptosome. Innenkorn (Meves). Dunkler Inner zone of acro- 
Teil des Mitosomes (Niessing), some (IZA). 
Spermiocalyptra. Spitzenknopf or Spitzenkérper Acrosome (4). 
of German authors. Acrosom 
of v. Lenhossék. 
Spermiocalyptro- Kopfkappe of German authors. Covering membrane 
theca. of acrosome (CA). 
Idiophtharto- Archiplasmarest (Benda). Idio- Golgi elements with 
some (Idio- zomrest (Meves). archoplasmic re- 
ectosome) mains (GA). 
4, TECHNIQUE. 
The guinea-pigs used for this work were nearly all supplied 
to us by Mr. H. M. Carleton and Mr. J. S. Haldane of New 
College, Oxford, to whom our thanks are given. 
We used especially the Golgi apparatus techniques of Cajal 
and Mann-Iopsch, as well as many other methods. One of 
us (J. H. W.) carried out a large number of tests with the 
Cajal method in order to ascertain the best time to leave the 
testes in the formalin fixative. It was found that twenty-four 
hours in the fixative and twenty-four hours in the silver bath 
gave the best results, though it was always very difficult to get 
really satisfactory preparations with any of the formalin- 
silver nitrate methods. 
We used the methods of Stockard and Papanicolaou with 
fairly satisfactory results, but never got preparations quite 
so clear as drawn in their figures. At a later stage in this work 
we tried Da Fano’s new cobalt formalin method, which gave 
useful results. We also made some excellent Mann-Kopsch 
preparations (three hours Mann’s fluid, two weeks 2 per cent. 
OsO,), but Flemming without acetic acid and Champy gave 
poor results. 
