128 NEOTROPICAL PSELAPHIDAE 



Louisiana [glaber] and Alabama and Florida {rufus). It would be of interest 

 to study the types of all the species to see if glaber were more nearly related 

 to the Mexican species and rufus more nearly related to the Antillean species, 

 or if both arose from one or the other stem. Such data might throw light on 

 the possible migration route northward. 



Apparently glaber is penetrating northward up the Mississippi valley, since 

 I have collected it near New Columbia, Illinois, the most northern record of the 

 genus to my knowledge. 



Tentative Key to Neotropical Species 



Posterior coxae slightly oblique mesially, the metasternum appearing 

 between them as a truncate edge, the coxae slightly separated 2 



Posterior coxae not mesially oblique, the metasternum appearing be- 

 tween them as a minute, obtuse point, the coxae practically con- 

 tiguous 4 



2. Ninth antennal segment as long as tenth antennal segment 



niexicanus 



(1.3-1.5 mm.; Mexico) 

 Ninth antennal segment shorter than tenth antennal segment 3 



3. Tenth antennal segment two times as long as ninth segment . gibbicollis 



(1.6-1.7 mm.; Mexico; eleventh antennal segment 

 as long as second to tenth inclusive combined) 



Tenth antennal segment three times as long as ninth segment 



longicollis 



(Bogota, Colombia; 1.8 mm.) 



4. Known only from Mexico grouvellei 



(1.2-1.4 mm. long; Mexico; segments of antennae IX and X lentic- 

 ular, XI ovate, acuminate, shorter than in mexicanus ; male last 

 sternite lightly, longitudinally sulcate) 

 Known only from the Antilles 5 



5. The last three described species are not separable with any certainty 



without recourse t,o the types: 



a. -polity^ Reitter. St. Thomas, Virgin Islands. 



Ninth and tenth antennal segments less lenticular than in grou- 

 vellei; eleventh segment longer and less ovate than in grou- 

 vellei. 



b. dominicanv^ Schaufuss. Hispaniola (probably Haiti as the citation 



is Saint-Domingue) 

 Said to be similar to grouvellei and polity^ but the antennae are 

 lost from the type (only known specimen) according to 

 Raffray, 1896. 



c. gracilis Raffray. Grenada, Windward Islands. 1.0-1.1 mm. long. 



Near politus, but the ninth and tenth segments of antennae are 



