EMBXOPTERA OF THE NEW WORLD — ROSS 405 



gites subequal, each usually bearing a small, poorly developed, simple 

 process; ninth sternite and process symmetrical; vestiges of para- 

 procts present, especially those of the left; vestiges of both cercus- 

 basipodites present in ventral membrane; cerci large, simple, not 

 clavate, equal, nonechinulate. 



Females. — Very large (15 to 20 mm. long) ; uniformly medium 

 brown; antennae brown with several terminal segments white. Oc- 

 cipital foramen acutely pointed apically. Prothorax broad, with a 

 longitudinal pale streak on each anapleurite extending from apophys- 

 eal pit to anterior dorsal margin. Hind basitarsi elongate, wdth two 

 prominent sole-bladders. 



Genotype. — Einhia nobilis Gerstaecker, by original designation.^ 



Distribution. — Kecent: Northern South America. Tertiary: Mio- 

 cene (?), Florissant of Colorado. 



Remarks. — Specimens of this easily recognized genus appear to be 

 rare in collections. The numerous occasions on which specimens 

 (mostly immature) have been collected in plant quarantine among 

 orchid roots seem to indicate that this is a favorite habitat of the 

 genus and one to be carefully investigated by field collectors. 



In many features, particularly the simple structure of the male ab- 

 dominal terminalia, Clothoda easily ranks as the most generalized 

 group of the order. The species, unlike those of most other genera, do 

 not seem to have constant intraspecific characters ; even wing venation 

 is subject to individual variation. There is a great need for studies 

 based upon large numbers of specimens from scattered and single lo- 

 calities, in order to test the constancy of certain characters. The writer 

 provisionally recognizes three Recent species and one subspecies at 

 this time. These may be differentiated as folloATs : 



KEY TO SPECIES OF CLOTHODA (MALES) 



1. Tei-tinry, Florissant of Colorado florissantensis 



Recent, northern South America 2 



2. Tenth abdominal tergite entire, without a median cleft or caudal processes; 



Brazil nobilis 



Tenth tergite medially cleft ; each heniitergite thus formed bearing a small 

 but distinct process 3 



3. Wings with Cuia usually unbranched ; Trinidad urichi urichi 



Wings with Cuia 1- or 2-branched ; South America 4 



4. Cu la with two bi'anches : process of left hemitergite curved mesad at apex ; 



membranous median cleft of tenth tergite extending to basal margin ; second- 

 ary process of right hemitergite (10 RP2) attached basally to right hemi- 

 tergite (10 R) ; Venezuela urichi intermedia 



Cuia with one branch ; 10 LP curved outward at apex ; membranous medial cleft 

 not attaining basal margin ; 10 RP2 free, not attached to 10 R ; Colombia 



aequicercata 



1 Enderlein's concept of this species was based on a specimen from Fonte Boa, Brazil 

 (800 miles from the type localit.v of nobilis), deposited in the Stettin Museum. 



