MUTILLA.— SPH^EOPHTHALMA. 313 



above the middle. The recurrent nervures are received in the apical third of the 

 cellules ; the transverse median nervure is interstitial. 

 A very distinct little species. 



1 62. Mutilla gracilis. 



Mutilla gracilis, Smith, Cat. Hymen. Ins. iii. p. 42* j Blake, Trans. Am. Ent. Soc. iii. p. 231% and 

 xiii. p. 202 3 . 



Hob. North Ameeica, Texas 2 3 . — Mexico 2 3 . — Amazons, Para x . 



Smith l does not describe the form of the eyes, nor of the petiole of this species. It 

 is placed in this section by Blake 3 , who also, as noted above, records it from Texas and 

 Mexico ; but he merely gives an abstract of Smith's description of the insect. If it 

 really belongs to this section, it differs from M. herberti and M. blakei in having the 

 wings hyaline, with the apical margin clouded ; the tegulse produced behind and ridged 

 down the middle ; the head covered only with a thin griseous pubescence. 



SPHCEROPHTHALMA. 



Sphcerophthalma, Blake, Trans. Am. Ent. Soc. iii. p. 232 (1871) ; xiii. p. 180 (1886). 



As in Mutilla, this genus may be conveniently split up into two sections ; one having 

 the basal segment of the abdomen gradually dilated to the apex and confluent with the 

 base of the second ; the other having it much narrower than the second and not, or 

 hardly, dilated at the apex. The first section may be further subdivided by the form 

 of the head, of which, as will be seen, there are three well-marked types. 



So far as we can judge from the collection at our disposal and from the small number 

 ' described, the males appear to be much rarer than in Mutilla. They are easily known 

 from the latter by the eyes being entire. 



A. The basal segment of the abdomen gradually dilated to the apex, and 

 confluent with the second. (Species 1-66.) 



i. The posterior angles of the head rounded, acutely produced beneath. (Species 1-8.) 

 a. The cheeks with a large tooth on either side. (Species 1-7.) 

 l. Sphaerophthalma robinsoni. 



Mutilla robinsonii, Blake, Trans. Am. Ent. Soc. iii. p. 250 \ 

 Sphcerophthalma robinsonii, op. cit. xiii. p. 246 2 . 



Hab. Mexico (Sumichrast 1 2 ). 



This species appears to be closely related to the following, S. respublicana, but 

 differs from it in the " cheeks below the eyes having two small bilobed tubercles, ferru- 

 ginous in front, just beneath which there is a stout tooth on each side projecting 

 behind, ferruginous at tip; below these are two others much larger, projecting beneath." 



biol. cente.-amer., Hymenopt., Vol. II., November 1894. 2 ss 



V 



