136 NEOTROPICAL PSELAPHIDAE 



flight may have had a definite dispersal value, especially when their cosmopoli- 

 tan distribution is noted. Poor flght for one sex, as in the case of many Jubus, 

 would prove to be a restrictive factor in species dispersal as much as poor flight 

 for both sexes, and it is of interest to again point out the parallel development 

 of large eyes and wings in so many instances, or the converse of rudimentary^ 

 eyes and wings in one or both sexes within the family. A few of the neotropical 

 species have a moderately wide distribution, sallaei being reported from 

 Mexico, Guatemala, and Panama, parviceps with the same general range, celata 

 from Mexico, Guatemala and Nicaragua, reichei from Guatemala and Co- 

 lombia. With wide geographic ranges known for certain species of the genus, 

 structural characters become of great importance in separating new species, 

 since similar specimens from relatively distant localities may represent either 

 the same species, or variations within the same species population. 



The genus as a whole was separated into at least seven valid divisions and 

 sixty species groups by Raffray in 1904. The addition of new species since that 

 time has increased the number of groups holding neotropical species. Probably 

 a new group will have to be formed to hold femoralis Fletcher, and one species 

 has been placed in a new genus {vide infra). Three of Raffray's seven divisions, 

 and eighteen out of sixty species groups, contain neotropical representatives of 

 Reichenbachia. The following arrangement is based upon Raffray's 1904 treat- 

 ment, and deals only with these neotropical species groups. Unfortunately, such 

 keys place emphasis upon the male sex, and in most instances the females of 

 this genus must be assigned by association rather than by exact structural detail. 

 Among the neotropical species there are seven groups in which both sexes have 

 the head, mandibles, antennae, pronotum and legs simple and unmodified. In 

 these groups the males and females are difficult to separate. In such cases direct 

 dissection to expose the copulatory organs, or cleared slide mounts to examine 

 the latter, will settle the question of the sex of specimens; where a series is 

 available this method of direct examination of one or two specimens is necessary 

 to correlate minute structural differences with sex. These methods have been 

 fully discussed in the section on preparation of material for study. The fifth 

 visible (most distal) sternite is large in the genus, and subject to some varia- 

 tion. Such variation is especially found in the males and consequently proves 

 helpful in separation of sexes in the seven groups noted above; the male fifth 

 sternite is often laterally sinuate, or concave medianly, this concavity varying 

 from a simple, even depression to a longitudinal impression. The males of the 

 other groups are strikingly marked, with abnormal antennae, or front, or legs 

 in various combinations, often grotesque and frequently very^ similar in allied 

 species. In the following tentative key I have relied chiefly on structural char- 

 acters of the male sex; the Roman numerals refer to the 1904 Raffrayan group 

 number. 



Key to the Neotropical Species Groups 



Species in which both sexes are essentially normal in most particulars, 

 and agree in the following essential items: (1) the vertex has three 



