NORTH AMERICAN HYMENOPTERA. 291 



A question remains as to albijjes. Mr. Fox suggests that it may 

 perhaps be the same as nubecula, though Cresson does not mention 

 the abdominal bruslies ; or it may, he adds, be the new form pieus. 



It seejns to me that in all probability albipes is a good species, and 

 I am sure it cannot be picas. 



The picus-nubecula-belfragei group is recognized by the large fus- 

 cous cloud, varying in intensity beyond the marginal cell. But 

 albipes is said to have the marginal cell itself with a fuscous cloud, 

 and nothing is said of any beyond. To further distinguish albipes 

 from ^9ic»« are the three submarginal cells, picus having never more 

 than two. 



The following table will serve to separate the species allied to 

 picas, which are found in the Mesilla Valley: 



A.— stigma inconspicuous, very pale yellowish : two submarginal cells and two 

 recurrent nervures. 



1. Head concolorous with body P. belfragei Blake. 



2. Head black P. belfrag-ei var. mehndceps (Blake). 



B. — Stigma brown, conspicuous. 



1. Three submarginal cells and two recurrent nervures- .P. nubecula Cress. 



2. Two submarginal cells and only one recurrent nervure- . . .P. picus C'kll. 



A word may be added to the generic name employed, Mr. Fox 

 having pi-oposed to merge Fhofopsis in Sphierophthalma. To me, 

 genera are mainly a matter of convenience ; and as Sp/uerophthalma 

 is already inconveniently large, it seems suitable to distinguish from 

 it such a series as Photopsis, which is easily recognized by its peculiar 

 fades, and, moreover, differs from SpJmrophthalma in being (like 

 Brachijcistis) strictly nocturnal. It may be that some supposed spe- 

 cies of Sjjhcerophthalma are really females of Photopsis. Thus I 

 found a single specimen at Las Cruces, New Mexico, which Mr. Fox 

 tells me is Sp/uerophthalma marpesia BL, thougli small. To me it 

 appears to be the female of Photopsis concolor, which is connuon in 

 the same vicinity. But, as Mr. Fox observes, there is no way of 

 proving this at present, and S. marpesia must be held distinct. 



BrachyciMtis perpunotatUN n. sp. -J,. -Nearly 6 mm. long, perfectly 

 black, excejit the dark Ijrown antennae and tarsi, the ferruginous mandibles, and 

 the lateral margins of the dorsal abdominal segments shining ferruginous in cer- 

 tain lights; the tegulse are shining black; the large stigma is black, the veins 

 dark brown, the wings quite clear. Antennse. long, first and second joints of 

 flagellum practically equal, the second perhaps a little the longer. Head, thorax 

 and abdomen shining, with sparse whitish hairs, most perceptible on the abdomen : 

 the whole body surface is rather sparsely, but very strongly punctate, the punc- 

 tures on the mesothorax being very large ; the first abdominal segment is large, 



TEANS. AM. ENT. SOC. XXII. AUGUST, 1895. 



