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EXPLANATION OF PLATES. 
All the photographs, except No. 17, Plate I, were taken from our modified 
smear preparations of the testes of Anasa tristis at a magnification of 1000 
diameters. The Zeiss Apo., 2 mm. immers lens, 140 apr. and compensating 
ocular 4 were used with camera draw of 25%4 inches. 
The preparation were stained with a saturate solution of Bismark brown. 
The reproductions are bromide prints made by the Rotograph Company 
from our own negatives. 
PLATE I. 
Puoto. 1. Rest stage of spermatocyte ist order, showing diffused chro- 
matin and round plasmosome. 
Puoro. 2. A little later stage than Photo. 1. The chromatin in this cell 
shows a slight indication of a network and the plasmosome has the typical 
round form. 
PuHoto. 3. Resting spermatocyte about the same stage as above showing an 
elongated plasmosome. 
Puoros. 4 To 8. Resting spermatocytes showing different stages in the 
formation of the chromatin network. All the plasmosomes have the typical 
round form. 
