192 Kev. T. A. Marshall's monograph of 



apex in the ? ; 8 segments visible above ; 1st linear, elongate, with 

 basal tubercles ; 2d and 3d a little shorter ; the rest transverse ; 

 belly carinated ; anus J truncated ; ventral valve produced, obtus- 

 angular. Terebra longer than the body, seldom shorter. 



The species are black, with or without rufous or testa- 

 ceous markings ; hut M. abdominalis is often wholly 

 testaceous. The general form much resembles that of 

 Lissonota and Glypta among the Ichneumons. The 

 Macrocentri are parasites of Lepidoptera, and often 

 gregarious in large numbers ; one species has been 

 reared from Anohiwn. The habits of three species are 

 noticed by Eatzeburg, and he has mentioned seven more 

 supposed to be different ; but their descriptions are 

 incomplete, and some of them may be mere varieties. 

 Brischke found the larvae of M. inter stitialis, Ratz , in 

 small colonies between leaves of Pyrus aria (White 

 Beam-tree). Some individuals retired from the rest, 

 and made their cocoons separately. It is not stated 

 what insect had been their victim. On the 22d of July 

 these larvsB were 2|- lines long, white, with a green 

 intestinal canal ; on the 8th of August the perfect insects 

 appeared. The cocoons are narrow and elongate, brown, 

 silky, and when agglomerated together they are covered 

 with a whitish web common to the whole brood ; but the 

 solitary cocoons are not so protected. 



Table of Species. 



(6) 1. Antennas 45 — 54-jointed ; maxillary palpi 



elongate, 3d joint as long as the 1st of the 

 flagellum, or longer. 



(3) 2. Third abdominal segment (like the 2 pre- 



ceding) entirely rimulose . . . . . . 1. abdominalis, Fab. 



(2) 3. Third abdominal segment rimulose at the 



base only, or entirely smooth. 

 (5) 4. Thorax black ; stigma fuscous .. ..2. marginator, Nees. 



(4) 5. Thorax rufous ; stigma yellow . . . . 3. thoracicus, Nees. 

 (1) 6. Antennas 30 — 37-jointed ; maxillary palpi 



short, 3d joint shorter than the 1st of the 

 flagellum. 

 (8) 7. Second abscissa of the radius as long as the 

 1st intercubital nervure ; legs short, stout ; 

 mesonotum J black ; terebra longer than 

 the body . . . . . . . . . . 4. infirmus, Nees. 



(7) 8. Second abscissa of the radius much shorter 



than the 1st intercubital nervure ; legs elon- 

 gate, slender ; mesonotum J rufous ; terebra 

 not longer than the abdomen . . . . 5. collaris, Spin. 



