Superfamily Avicularioidea 



DD. Posterior sigilla small or of moderate size and 

 much farther from each other than from the margin 

 of the sternum. 

 E. Anterior tarsi and metatarsi short, equal; meta- 

 tarsi unarmed except by apical spines. P. 240. 



Amblyocarenum 



EE. Anterior metatarsi longer than the tarsi and armed 



below with many spines. P. 241 Aptostichus 



Genus PACHYLOMERUS (Pach-y-lom'e-rus) 



As indicated in the table above, this genus differs from the 

 other genera of this subfamily by the presence of a deep de- 

 pression in the basal 

 part of the upper sur- 

 face of the tibia of 

 the third pair of legs 

 (Fig. 219). This de- 

 pression is smooth, 

 and of a deeper colour 

 than the remainder of 

 the segment; on each 

 side of this depression 



Fig. 219. TERMINAL PORTION OF THE THIRD t L„ r . • „ nsrrrvw 



LEG OF PACHYLOMERUS there 1S H narrOW 



membranous line. 

 The figure represents the tibia of a female. In the only male that 

 1 have seen the depression in this segment is not so marked as in 

 the female; and the membranous line is wanting. 



The representatives of this genus are common in the warmer 

 parts of the United States. Their burrows are furnished with 

 doors of the wafer type. Several species have been described 

 from the southern Atlantic States, one from Arizona, and one 

 from California; but as yet insufficient material has been studied 

 to make it possible to indicate with any degree of certainty the 

 distinctive characteristics of the species. 



Pachylomerus audouinii (P. au-dou-in'i-i). — The most com- 

 mon species of Pachylomerus in the southeastern part of our terri- 

 tory is believed to be the one described by Lucas in 1837 under 

 this specific name. It is a large species, the body of the adult 

 measuring one and one third inches in length. 



236 



