248 ORTHOPTERA. 



Synopsis of the Species of Rhicnoderma. 



A. Larger ( ? , length 40-50 mm.). 



b. Body everywhere strongly punctured, the surface dull or sub-shining. 

 Median carina of pronotum conspicuous. 

 c. First abdominal segment concolorous with the rest. Hind tibiae 



ferruginous, the genicular area of the femora olive-brown .... 1. olivacea, Gerst. 

 cc. First abdominal segment testaceous. Hind tibiae dark brown, the 



genicular area of the femora black 2. basalis, sp. n. 



bb. Body less strongly punctured, the surface decidedly glabrous. Median 

 carina of the pronotum nearly or quite obliterated. 

 c. Pronotum furnished with but two continuous transverse sulci. Hind 

 femora without black markings. The hind tibiae pale, internally 



tinged with dull orange, their tarsi concolorous 3. glabra, sp. n. 



cc. Pronotum provided with three continuous transverse sulci. Hind 

 femora with their genicular portion strongly marked with black. 

 The hind tibiae internally and apically black, externally vinaceous, 



their tarsi crimson 4. pugna.v, sp. n. 



AA. Smaller ( ? , length 32 mm.) . 5. humilis, Rehn. 



1. Khicnoderma olivacea, Gerstaecker. 



Rhicnoderma olivacea, Gerst. Mittheil. naturwiss. Ver. Neu-Vorpomm. und Rugen, xx. p. 20 



(1888) \ 



Hab. Panama, Chiriqui 1 . 



This insect, which may be considered the type of the genus, has not been seen by 

 me. It is quite evident that the different species are rather local in their distribution, 

 or else the forms tabulated above are representatives of a very variable single species 

 which enjoys a wide range over tropical portions of northern South America, Central 

 America, and Southern Mexico. 



2. Khicnoderma basalis, sp. n. 



As indicated in the synoptic table of the species, the present form is most nearly related to R. olivacea, from 

 which it differs by its pale first abdominal segment, the complete absence of glossiness upon the head and 

 thorax, and by its brownish (instead of greenish) general colour. The vertex and borders of the eyes 

 are entirely punctate, instead of containing spaces which are smooth. As compared with T. humilis, the 

 eyes are smaller and the lower portion of the face longer and broader, the vertex is without the V-shaped 

 carinse that meet in the centre of the upper edge of the frontal costa, while the lateral foveolae above the 

 antennae are quadrate and unusually deep. The frontal costa is both profoundly sulcate and deeply and 

 closely punctulate, and provided a little below its middle with a prominent transverse carina that 

 separates it into two compartments ; at the transverse groove of the face the costa suddenly narrows to 

 less than one-half of its width above, gradually diminishes in height and depth of sulcation, and continues 

 to the base of the clypeus. The latter is short and strongly wrinkled and punctured. The labium and 

 mandibles are large and prominent. The pronotum is transverse, very strongly and closely punctate, the 

 transverse sulci fairly impressed ; the median carina is distinct but severed by all four of the sulci. The 

 metathoracic segment is much shorter at its sides than above, while its middle is rather deeply and broadly 



