102 U.S. NATIONAL MUSEUM BULLETIN 266 



and Atwood in western Kansas. The host plants comprise the Cylindro- 

 puntia 0. imbricata and small prickly pears of the 0. tortispina and 

 0. polyacantha groups. 



Moneilema nigriventris Fisher 



Another small black species was described from adults collected by 

 officers of the Board on 0. tortispina at Dumas in the Texas Panhandle 

 in June 1926. Examples taken west of Carlsbad, New Mexico, in 

 June 1927, have been determined as the same species. 



Moneilema crassa LeConte 



This is a medium-sized black species with a wide distribution in Texas. 

 The reference by Hamlin (1926, p. 104) to this species is a misiden- 

 tification and should refer to M. ulkei. 



Material has been recorded from Texas at Pearsall, Uvalde, Del Rio, 

 west to the mouth of the Pecos River, San Antonio, thence in a northerly 

 direction to San Angelo, Sterling City, Big Springs, Lubbock, and 

 Dalhart, and to Tyrone in western Oklahoma. The life history and 

 habits have been studied at Uvalde, where the insect occurs rather 

 generally in company with M. ulkei in fields of Opuntia lindheimeri. 

 However, whereas M. ulkei is often prevalent, M. crassa has rarely been 

 encountered in numbers. 



Adults have been collected in April, May, June, and July, and on 

 one occasion in September. There is an annual generation, although 

 under cage conditions occasional adults have emerged in November 

 from eggs laid in June. Emergence occurs in April and May, com- 

 mencing earlier than that of M. ulkei. The beetles survive until July. 

 Oviposition extends from April to early July; the eggs are placed 

 singly in earth cells against the butts of the plants or beneath prostrate 

 segments. Many larvae reach full size and enter cocoons in September 

 and October, but do not pupate until after winter; other larvae continue 

 to feed and develop during the winter months. 



Moneilema aterrima Fisher 



This rather small species, black with the elytra variegated with white, 

 was described from a few examples collected at El Corazon near San 

 Luis Potosi, Mexico, in May, June, and July 1930 and in May 1931. 



Moneilema blapsides Newman 



A moderately large black species, this appears to be uncommon. A 

 few specimens were taken at Durango, Mexico, in October, and in 

 San Luis Potosi. 



