9 



inside. With so many maggots there is not food enough for all, 

 so the catoi-]Hllar dies too soon before the parasites can be- 

 come full-grown. Perhaps only those caterpillars which 

 have eaten but one egg, or have had but one egg hatch inside 

 of them, are able to survive till the maggot becomes full-grown, 

 and those having more than one maggot inside die too soon, and 

 thus the maggots themselves die; at any rate, I never have 

 reared more than one parasite per host, nor have I found more 

 than one puparium formed per host. 



In dissecting caterpillars containing maggots, I never have 

 found maggots feeding on the nerve ganglia, as Sasaki has; 

 hut I have found them located, as he says, near a spiracle of 

 the caterpillar, and enclosed in a sort of sac which is apparently 

 an enlarged tracheal tube, the maggot locating in it when small 

 and the tube becoming enlarged as the maggot grew. Usually 

 there is a blackening of the caterpillar externally where one of 

 these is located. Wlien about full-grown the maggot leaves the 

 sac and lies lengthwise in the caterpillar (or pupa, if it has 

 pupated) eating up all or nearly all of the fatty matter of the 

 latter. Tt may be nearly full-grovm at the time the caterpillar 

 pupates, or it may be still quite small ; but I never have known 

 of a case where the puparium of the parasite was formed before 

 the caterpillar had pupated. The puparium is cylindrical, 

 roTinded at the anterior end, and rather blunt at the posterior 

 end where it is often somewhat widened. It is of a very dark 

 reddish color, and each of the two spiracular orifices at the 

 posterior end has three black rounded protuberances around it. 

 The anterior end is always directed anteriorly in the host pupa. 

 The adult fly emerges in about 10 to 14 days from the time 

 the puparium is formed. 



APEIL 2nd, 1908. 



The thirty-ninth regular meeting was held in the usual place, 

 Mr. Giffard in the chair. 



NOTES AND EXHIBITION OF SPECIMENS. 



Refen-ing to recent notes on Pison vridipennis presented to 

 the Society by Mr. Swezey and others. Dr. Perkins stated that 

 after collecting and carefully examining specimens of this sup- 

 posed species, he is certain that it is not vridipewais and in 



