TKIDACTYLTTS. 205 



posticae flavae, supra in medio extus denticulis crassioribus 3-4 instructs. Tarsi omnes flavi ; antici et 

 intermedii apice fusci ; postici calcaribus tibiarum aequilongi. Abdomen supra fuscum, segmentis partim 

 flavo-limbatis ; subtus dense punctulatum, flavum, segmentis basi plus minus fuscis. Cerci fusci, secundo 

 articulo flavo, apice nigro. Appendices anales flavi, apice fusci. 



c? . Pedes antici (fig. 7) difformes. Femora anteriora dilatata, margine supero valde arcuato, infero triangu- 

 lato. Margo inferus coxarum apice bidentulus ; ille femorum totus crenatus, basi 4-dentulus. Tibiae 

 late furcatae, in partes duas divergentes divisae ; pars supera apice bispinosa, infera processum ingentem 

 subrectum, tarsum gerentem, apice ungue gracili arcuato longissimo armatum, formans ; (processus et unguis 

 apice fusci). Penultimum segmentum ventrale transversum ; ultimum fuscum, trapezinum. Appendices 

 anales sat fusiformes. 



Tar. a. Plus minusve ilavo-varius ; ore flavicante ; femoribus posticis vitta longitudinali vel maculis flavis ; 

 pedibus intermediis luteis fusco-maculatis ; pronoto supra lutescente. — b. Alis abbreviatis. 



Long. corp. 6, cum alis 6-5 millim. 



Figure. — Fig. 7, anterior leg of tbe male: /, femur; t, tibia; s, tarsus. 



Hab. North Ameeica, Southern and Western States, Texas (Boll). — Guatemala, San 

 Gerdnimo (Champion). 



The very extraordinary form of the anterior tibiae of this species should be well 

 understood. The tibia is very broadly and deeply emarginate at its superior edge, and 

 thus divided into two divergent branches. The upper branch terminates in two spurs. 

 The inferior branch (t) is very elongate and attenuated at the tip : thus it has lost one 

 of its spurs, and the other spur has grown to an enormous size, forming a regular claw. 

 This branch bears the tarsus (s). 



Obs. 1. — Burmeister, in his diagnosis of this species, describes the anterior tibiae in 

 an unintelligible manner. It would appear that in his insect a tibia had been broken 

 off and repaired by gluing the end of the inferior branch (t) to the femur ; thus he 

 could regard the tibia as being very thin at the base and dilated at the end . . . \ 



Obs. 2. — It has been stated that T. apicalis is found also in the East -Indian region. 

 This is a mistake ; it is a purely American species. The Indian insect referred to 

 T. apicalis belongs to a different species, well characterized by the form of the anal 

 pieces of the abdomen, which greatly resemble those of T. mixtus. 



Obs. 3.- — It is a question whether the extraordinary form of the anterior tibiae is 

 characteristic of the males only, or common to the two sexes. If it is peculiar to the 

 males, T. incertus (no. 3) might prove to be the female of T. apicalis. 



2. Tridactylus fissipes, Sauss. 



Tridactylus fisslpes, Sauss. Miss. Scient. Mex., Orthopt. p. 352. 3, t. 8. figg. 25, 25 a (<?). 



Nigro-aeneus ; corpore immaculato. Antennae fuscae vel fusco-annulatae. Elytra in dorso testacea. Alae 

 fusco-testaceae, abdominis apicem attingentes. Pedes antici testacei, tibiis fusco-marginatis ; inter- 

 mediorum femora et tibiae fusca, margine infero flavo, femoribus apice, tibiis basi et apice flavis ; femora 

 postica fusca, apice flavicantia, margine infero flavo ; tibiae flavae. Tibiae posticae supra in medio, saltern 

 extus, denticulis minutis 3-4 armatae. Tarsi omnes flavi, vel apice puncto fusco. Metatarsus posticus 

 calcaribus sequilongus. Cerci nigri, apice longiuscule flavi vel testacei. Appendices anales graciles, 

 teretes, fusci, basi rufescentes. Long. 7*5 mill. 



$ . Tibiae anticae haud difformes, sed margine apicali V-formiter inciso, ac 4-dentato, calcaribus in apice dentium 

 exsertis. 



