208 



THE SOLITARY WASPS. 



}>y chloroform, by pricking them between the pro- and meso- 

 thorax, by decapitation or other means. 



Resume of Observations on Fifteen Nests. 



When the bees are taken from freshly provisioned nests be- 

 fore the egg has hatched the muscles may remain fresh until 

 the eighth day or even to the ninth or longer, but in some cases, 

 all other things being equal, dryness appears on the fifth day, 

 and is complete on the seventh. Out of thirteen cases four were 

 completely dry on the eighth day. The bees which were caught 

 and killed began to dry at once and dryness was usually com- 

 plete on the fifth day. 



Andrenae, which are sometimes found in the nests, were 

 given to Cerceris instead of Halyctus, with the result that they 

 always dried more rapidly (in four or five days.) 



Finally the contents of each of some freshly provisioned nests 

 have been separated into two parts, one of which was submitted 

 for five minutes to the vapor of chloroform in a tightly corked 

 flask while the other remained intact. Those that had been 

 chloroformed did not dry more quickly than the others. In 

 some cases the chloroformed ones were still fresh when the 

 jthers were perfectly dry. This experiment goes to show that 

 a good part of the bees are really dead. One may object that 

 they are in a state of numbness analogous to hibernation, and 

 that as they are scarcely breathing they are not affected by chlo- 

 roform. Possibly this objection is well founded but it is none 

 the less true that this state of numbness is of very short dura- 

 tion, sometimes scarcely perceptible. 



The bees, then, are not preserved for a month and a half. 

 They die in ten days or even in a shorter time. 



Bees are sometimes found in the cell occupied by the larva of 

 Cerceris, which have plainly been dead a long time although 

 they appear intact and show no lesion attributable to the larva. 

 The length of time that it takes the larva to develop is not 

 known. The eggs which have been found fastened to bees have 

 not hatched or have hatched and then died. One of these eggs 



