160 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.40. 



accentuated. The anterior transverse and pleural sutures are 

 especially well marked and completely interrupt the patterns of the 

 superficial network. The pleurae are distinctly wider in front, the 

 forebelt being narrowed and shortened below. 



Last segment of much the same shape as in 0. dentatus; surface 

 of the segment and the valves less rugulose and more distinctly 

 punctate. 



Morphological interest warrants the description of the peculiarities 

 of this animal, though more abundant material must determine 

 whether they have taxonomic importance or not. 



Genus CYCLOTHYROPHORUS Pocoek. 



Cyclothyrophorus Pocock, Biologia Centr.-Amer., 1908, p. 83. 



The Mexican genus Cyclothyrophorus, established by Pocock on 

 C. salvini from the Mexican State of Guerrero, may belong to the 

 same general group as Onychelus and Eurelus. The anal valves have 

 the same peculiarity of meeting in a reentering angle or groove, and 

 the anterior corners of the first segment are cut away so as to expose 

 the sides of the mandibulary stipes. Nevertheless, if the character- 

 istics of the type species are taken into account, the genus Cyclothy- 

 rophorus appears to be quite distinct from the more northern types. 



The body of C. salvini is described as slender, less than 3 mm. wide 

 and over 12 times as long. The antennae are crassate, with the second 

 and third joints about equal in length. The first segment is "with- 

 out trace of a sulcus" to define an anterior margin. Second seg- 

 ment "projecting below the level of the first." The coxae of the 

 third pair of legs of males are without processes, and the ventral plate 

 of the gonopods is not produced, fully exposing the oblong anterior 

 lobes. 



The form of the body, the absence of processes from the third pair 

 of legs of the males, and the form of the coleopods seem to ally 

 Cyclothyrophorus with Onychelus rather than with Eurelus. 



ANELUS, new genus. 



Type. — Anelus reduncus, a new species from south Texas. 



Diagnosis. — Remotely related to Onychelus and Eurelus, but 

 readily distinguished by having the first segment very broad, with 

 two nearly square lateral corners, the body segments with densely 

 reticulate forebelt and coarsely punctate hindbelt, the last seg- 

 ment with a produced triangular apex, the anterior male legs with- 

 out coxal processes, and the ventral plate of the copulatory legs 

 rudimentary. 



Description. — Body rather small and robust, nine or ten times as 

 long as broad, cylindrical, slightly thicker in front, rather abruptly 

 tapered behind, coiling into a close spiral. 



