276 Proceedings of Indiana Academy of Science 
PLATE 1 
DEVELOPMENT OF METASTRONGYLUS APRI 
Pirst Week 
bee ee SEE ee 
.30 X .01 mm. eae 
-05 X .O2 mm. 
Second Week 
Cm Se he 
40 X .025 mn. 
.45 X .015 mn. 
Third Week 
-62 X .025 mn. 
-55 X .03 mm, 
DEVELOPMENT OF METASTRONGYLUS APRI 
The eggs are intended to show the various developmental stages. 
The larvae show actual measurements, and were drawn by means of the camera lucida. 
these enzymes. Thus, two-weeks-old larvae individuals were not digested 
when left in these ferments for 24 hours. On the other hand, young 
embryos were all killed after five hours, unless they were protected by 
the egg membranes. Likewise, when subject to weak antiseptics of 
different kinds, the same general results were obtained. Freezing 
seems to kill at all stages of development, but experiments with dessi- 
cation haye shown that two-weeks-old larvae can withstand prolonged 
drying out without injury. Such larvae were revived three months 
