201 



pupae of tlic Acnleatcs worv ])la('('(l for ('xjx'riuiciiiiil |)urposes. 

 At this time 1 should judge that the hirvae of ticeUplivoit, are 

 more susceptible to attack froui these parasites than that of the 

 Odynenis. M. haivaiiensis has previously been bred from the 

 larvae of Scelipliro)i caonentarium, Odynerus nigripennis, 

 Pison hospps and Megaclille palmarutn. It is quite probable 

 that this rhaleid and others are, to a more or less extent, ac- 

 countable for the occasional rarity of many species of our en- 

 demic wasps. 



A careful study of available literature on the Eumenids (un- 

 fortunately confined here to three works) leads me for the 

 present to determine this newly introduced wasp as Odynenis 

 nasidens Latr. If it is not that species then it is either 0. siin.pli- 

 cornis Sauss., or a variety of one or the other. 



Saussure in his Synopsis of Am. Wasps, Pt. I, pp 228-229, 

 1875, places the 0. nasidens of Latreille in his Division Paclio- 

 dynerus (also see Sauss. Mon. des Guepes Sol. p. 169, 1852, and 

 Supl. pp. 229, 252, 1850, Division Epsilon), this division of the 

 Odj'nerus having the antennae of the males simple, that is, not 

 terminated by a hook. He has described three species iu the 

 Section of his Division ParJi odynerus to w'hich 0. nasidens be- 

 longs, viz. : — 0. hrevithorax, Sauss, 0. nasidens, Latr., and 0. 

 simplicornis, Sauss. All of these three species evidently have a 

 close resemblance to each other and Saussure himself states that 

 without comjDaring numerous specimens of each of the species 

 one easily confounds all under the same description, taking them 

 for 0. nasidetis of Latreille. He further states that even after 

 the examination of his numerous specimens he still remained in 

 doubt although he thouglii that he could distinguish 0. hrevi- 

 thorax (piite clearly and in consequence determined it as a new 

 species. On the other hand in referring to his 0. simplicornis 

 he admits that "one should perhaps consider this species as a va- 

 riety of 0. nasidens." LTnfortimately there are no named speci- 

 mens of foreign Eumenids available locajly for reference pur- 

 poses so that a comparison of such with either tables of genera 

 or species is altogether impossible. The available literature on 

 the subject is also incomplete and because of these facts I have 

 sent a small series of both sexes of this introduced w^asp to the 

 U. S. i^ational ]\ruseum at Washington. In due course we will 

 no doubt secure a conclusive determination of the species. 



According to Saussure, 0. naside)is and its close allies are 

 species peculiar to tro])ical America, 1st — from the hot parts of 

 Mexico, 2nd — from (V)lonibia and Venezuela, ''Jrd — from Bahia 



