314 PROCEEDINGS OF THE NATIONAL MUSEUM vol. loe 



If oue is inclined to emphasize tlie direction of the postvertical 

 bristles, as is customary in making family distinctions among the 

 Acah'ptratao, then Lathcticonnjia cannot possibh' be placed among the 

 Clusiodidae. Further evidence for its separation comes fmm the bare 

 mesopleura, two costal breaks, five paii-s of doi-socentrals, longitudi- 

 nally excavated front, minute haire on upper face, etc. 



Acartophthulmus might, with considerable justification, be removed 

 from the Clusiodidae. Its general appearance is not that of a clusiid, 

 the arista is clearly inserted basally, the vibrissae arc scarcely larger 

 than the following oral haii-s, the humeral costal break occurs nowhere 

 else in the family, while the distal costal break, found in all other 

 clusiids, is lacking here. In addition, the large, widely spaced post- 

 verticals, the widely separated apices of the auxiliary and first 

 longitudinal veins, and the three simple reclinate orbitals represent 

 features which are not approached elsewhere in the family as far as 

 I have been able to detennine. Thus, should Acartophthalmns be 

 removed from the family, at least two features of Latheticomyia 

 listed above as indicative of a possible relationship to that family 

 would then be elmiinated. 



Continued discussion of a possible clusiid relationship seems 

 unnecessar}'. The following brief list of the essentially nonclusiid 

 characters will serve to emphasize the disparities: (1) gross appear- 

 ance, including pigmentation patterns; (2) convergent postvertical 

 bristles; (3) twice broken costal vein; (4) dorsocentrals in three 

 postsutural and two presutural pairs; (5) bare mesopleura; (6) 

 longitudinally excavated front. 



Of the above characteristics, the last five are all deemed of con- 

 siderable importance in family disthictions. It is m}^ opinion that 

 the disparities noted above are too great, and that the inclusion of 

 Latheticomyia in the Clusiodidae is not justified. 



U. S. GOVERNMENT PRiNTJNS OTFICE: I9S1 



