162 Journal of Entomology and Zoology 



ation in each cell, went plowing through the whole row, and when 

 the timber was opened the next morning No. 1 was found in cell 

 No. 6 ready to tear away the last restraining wall. In some cases 

 the first to emerge did wait for a short time before beginning to dig 

 out, but this was not the rule. I think this matter is probably gov- 

 erned by the food supply. If these was a fragment left from the 

 larval feeding it will satisfy the newly-emerged one for some time, 

 but if not, it soon seeks a way out. These creatures seem to be 

 ravenously hungry upon their emergence (as might be expected 

 after sixty days of organization and development without taking 

 any food) and their first activity is a search for food. After search- 

 ing through their own tunnel and devouring what fragments remain 

 they do not fly at once but enter adjoining burrows and profit by 

 any morsel which may have been left by the early death of a neigh- 

 boring larva or the failure of an egg to hatch. 



The question has been raised as to a uniform position of the 

 males and females in the brood tunnel (Davidson, Ent. News, Vol. 

 4, 1892). I noted at least one exception to such a rule, the first 

 of one brood being a male and the first of another brood being a 

 female. 



Parasites : The most interesting of the parasites found upon this 

 species was one of the Bombyliidae, Spongostylum delila Loew, which 

 first appears upon the foodmass as a very minute but exceedingly 

 active larva. Even before the egg of the host is hatched this almost 

 microscopic intruder is found industriously creeping about, rearing 

 and stretching as if looking for a foe to conquor. For three weeks 

 or more it thus restlessly creeps about over foodmass, egg and 

 larva, feeding promiscuously, then finally settles down and, fastening 

 itself by means of its hooked beak to the sixth or seventh segment 

 of the Xylocopa larva (Fig. 12), it quietly feeds until its host is 

 devoured unless shaken loose by the writhing movements (noted 

 above) of the larva, when it soon reattaches itself and resumes its 

 quiet feeding . The parasite is four weeks, or more old when it thus 

 attaches itself and is found to be only three to five mm. in length. 

 For nearly two weeks more its growth can scarcely be noted except 

 by careful measurements so that at the age of five and one-half to 

 six weeks its length is but from four to five mm. Here a remarkable 



