1914.] NATURAL SCIENCES OF PHILADELPHIA. 143 



Distribution. — The present species is only known from tlie vicinity 

 of Brownsville in the arid tropical Tamaulipan section of the lower 

 Rio Grande Valley, Texas. The range of the species unquestionably 

 extends south into Mexico. 



Biological Notes. — This form was numerous in vine-covered hedge:^ 

 and tangles near old Fort Brown, Brownsville, where they were 

 heard stridulating at numerous points about dusk, but they were 

 extremely difficult to secure, owing to their surroundings, as they 

 always sought refuge within the tangled hedges when approached. 

 The stridulation is a faint tsikh, repeated at intervals of about twice 

 th6 length of the note. 



Morphological Notes. — From the evidence of the two males, the 

 median width of the disk of the pronotum is seen to vary somewhat, 

 in the paratype this being as much as two-thirds the caudal width 

 of the disk. 



Specime7is Examined. — 4; 2 cf, 1 9,1c?' nymph. 

 Brownsville, Cameron Co., Texas, July^l-August 3, 1912, (R. and 

 H.), 2 cf, 1 9 , 1 cf nymph. Type, allotype and paratypes. 



Dichopetala tauriformis n. sp. * 



This is a very peculiar and distinct species having no close relation- 

 ship to any other form in the genus, in the female sex showing some 

 affinity to falcata and in the male sex approximating pollicifera more 

 nearly than anything else. The peculiar appendage of the supra-anal 

 plate of the male, the anomalous cerci, the strongly depressed median 

 section of which, together with the elongate aciculate tooth which is 

 peculiarly curved, and the unusual structure of the distal section of 

 the shaft, as well as the very decided peculiarities of the subgenital 

 plate at once distinguish the male sex, while in the female the ovi- 

 positor is proportionately the longest and heaviest in the genus, the 

 subgenital plate with its lateral trigonal lobes also being quite 

 different from that found in falcata. 



Type: cf ; Mountains twelve leagues east of San Luis Potosi, 

 Mexico. (Palmer.) [Scudder Collection.] 



Description of Type. — Size above the average for the genus; form 

 moderately slender. Head with the occiput rather strongly declivent 

 to the fastigium and antennal scrobes; fastigium low, slightly com- 

 pressed, weakly sulcate dorsad, not touching the frontal fastigium; 

 eyes prominent, elongate ovoid, their length two-thirds that of the 

 infra-ocular portion of the gense. Pronotum weakly sellate, the 



