species of Tenthredinida and Cynipidce. 485 



the 2nd recurrent nervnre is received in the 3rd cellule, but almost 

 touching the 2nd transverse cubital nervure. Female. Length, 

 nearly 6 mm. 



Hah. Northern Sonora, Mexico {Morrison). 



Ptilia nigerrima, n. s. 

 Black ; the anterior tibise dirty white in front. Wings hyaline ; 

 ner\Tii-es and stigma black. Antennae a Httle longer than the 

 abdomen, covered with long hair. Sutures on vertex broad and 

 deep, and converging in front of the ocelli, shallow at the side of 

 the oceUi, deep and broad behind them. The 1st recurrent nervure 

 is received a little in front of the middle of the cellule ; the 2nd is 

 interstitial; 3rd cubital cellule a little broader than long. The 

 body is broad and thick ; the legs are covered with pale microscopic 

 dovra, and the knees incline to piceous. Male. Length, 5 mm. 



Hab. Northern Sonora, Mexico {Morrison). 



Ptilia luteiventris, n. s. 

 Black ; abdomen luteous ; knees piceous ; anterior tibiae dirty white 

 in front. Wings hyaline ; nei-^nires and stigma fusco-piceous. An- 

 tennae not much longer than the thorax ; covered with a microscopic 

 pile. The three cubital cellules are together shorter than the 

 4th ; the 1st recurrent nervure is received in the middle ; the 2nd is 

 interstitial ; 3rd transverse cubital nervure bent outwardly ; the 

 3rd cubital cellule broader than long. Female. Length, o'o mm. 



Hah. Northern Sonora, Mexico {Morrison). 



Ohs. I have placed the above -de scribed three species 

 in Ptilia, as I have defined it in Biol. Cent. Amer., 

 Hymen., p. 42, as the 2nd recurrent is received rather 

 in the 3rd than in the 2nd cubital cellule ; but these 

 species illustrate the difficulty of using the neuration in 

 generic definitions, for actually they are intermediate 

 between Ptilia and Dielocera. 



CYNIPID.E. 



• Aulax rufipes, n. s. 



Black ; the antennae and legs (including the coxaej red ; scape 

 somewhat infuscated; the abdomen at the base, the sides, and 

 ventral surface, of a more obscure red than the legs ; oral region 

 and mandibles (except at the apex) piceous-red. Head with the 

 vertex shining, finely punctured ; the face opaque, more strongly 



