2 BowDiTCH Oil Hydrocharis obtusatiis and Marjdalis olyra. 



On May 1, one of the cases either came open, or was torn 

 open in some way at the side, and under water. The eggs, 

 about a dozen in number, were attached by their ends to 

 that side of the case which rested on the surface of the 

 water, and were swelled and transparent at the lower 

 extremity; some appeared to have a dark streak down the 

 middle as if about to hatch. 



The interior of the case appeared to be fihed with eggs 

 glued or fastened together with silk, the whole forming a 

 compact spongy mass of a whitish-yellow color. 



The second case is more flattened and square ; on the 

 front it had a curious roundish disk-shaped spot or surface, 

 which appears to be for ihe purpose of adhering by suction, 

 to any substance it may come in contact with, so as to in 

 some degree prevent the case from floating away. 



May 4. The eggs described above appaar to have hatchsd, 

 the larvo3, however, still remaining in the eo^g case; they are 

 about 2-10 of an inch long, have two blackish, dorsal 

 stripes from the head to the tail, growino; fliinter towards 

 the lormer on which are two reddish dots (eyes?); the front 

 half of the body is brownish, with occasional hairs or minute 

 black streaks; the head and feet are both tipped with mi- 

 nute black spots, and the general apperrarce is blackish- 

 brown gradually fading away to the usual transparent white 

 tail. There are more than I at first supposed, but how- 

 many it is at present hard to tell, Avithout danger of hurting 

 them. 



May 7. The last emerged yesterday, and unless some 

 have been eaten there were not more than eight or ten. 

 The larva at this time is about 7-10 of an inch long; two 

 dorsal stripes run fiom the segment behind the head to the 

 tail; the head is large and flattened, eyes prominent, jaws 

 and mouth parts strongly developed, the maxillae reachirg 



