204 Miscellaneous. 



MISCELLANEOUS. 



On some Insects collected in the State of Chihuahua, Mexico. By 

 T. D. A. CocKERELL, Entomologist of the New Mexico AgriculturtQ 



Experiment Station. 



The species recorded below were collected by the writer partly in 

 May 1S93, under the circumstances mentioned in Ann. & Mag. Nat. 

 Hist., July 1893, and partly during an hour or two spent at Juarez 

 on Aug. 26, 1893. The latter locality is on the northern boundary 

 of the State, just across the river from El Paso, Texas. Montezuma, 

 the locality for some of the species, is the name of a station-house 

 on the Mexican Central Railway. 



The whole of the territory now considered strictly belongs to the 

 arid Sonoran region — a region, however, which is more diverse in 

 its fauna and tiora than might be expected from the unusually 

 uniform physical features. This diversity is perhaps to be accounted 

 for by the fact that it is the meeting-ground of the Neotropical and 

 Nearctic species, which mingle in different proportions according to 

 the trend of the valleys, the altitude, and so forth. Once the 

 Mexican tableland is left for the tropical sea-coast, the absolute 

 dominance of the Neotropical fauna is beyond question ; but on the 

 plateau it cannot be said that the Nearctic forms occur to the 

 exclusion of the Neotropical, although they certainly appear to have 

 the upper hand. The warfare, if we may so term it, is carried on 

 under peculiar conditions, owing to the inhospitable nature of the 

 country, and the contest becomes largely one of endurance. Thus 

 certain plants, such as the Argemone, may intrude into a zone (the 

 mid-alpine) of which they are not typical, simply from their ability 

 to flourish in waste and arid land. The same may be said of certain 

 Cactaceae, which at 8000 feet in Colorado look incongruous by the 

 side of pines, spruces, and poplars. 



The collections now enumerated may throw a little new light on 

 these matters, being in many cases apparently the first records of 

 the species from Mexico. 



COLEOPTERA. 

 I am indebted to Mr. H. F. "NVickham for the identification of 

 these. 



CoccinellidaB. 



1. Hyperaspis lateralis, Muls. 

 Juarez. 



2. Scymnus tenebrosvs, Muls. 

 Juarez. (Houston, Texas ; Arizona : WicJcliam.) 



3. Scymnus near cinctus, Lee. 

 Juarez. A fine red-brown species. 



Elateridse. 

 4. Anelastes Drurii, var. Latreillei, Leo. 

 Samalayuca. (New Mexico, Arizona, &c. : WicJcham. The 

 species goes to the mid-alpine in Colorado.) 



