52 
The Food Relations of the Carabidaj and Coccinellidce. 
September, give an average of forty-six per cent, of animal food, 
all insects excepting a few mites eaten by three of the beetles, 
and amounting to only one per cent, of the food. The insect 
ratio, as far as recognized, with the exception of a single Podura, 
consisted wholly of plant-lice, which amounted to thirty-five per 
cent., while the fifty-four per cent, of vegetable food contained 
only pollen of plants and spores of lichens and fungi, the pollen 
and spores occurring in about equal quantities. The former was 
chiefly from flowers of grass and composite plants, about seven 
per cent, of the first and fifteen per cent, of the second. One 
per cent, of the pollen of Polygonum, and a trace of the pollen 
of pine, both eaten by a single beetle, are the only other items 
under this head. Lichen spores, including Physcia, were reckoned 
at two per cent., and those of fungi at twenty-five per cent. At 
least two-thirds of the latter, eaten by nearly half the beetles, 
consisted of spores of Helminthosporium. 
Three specimens of this species, taken in the corn-field at 
Jacksonville, had eaten much smaller ratios of animal food, which 
amounted to only thirteen per cent., all insects. Traces of plant- 
lice were recognized, but no structures of chinch-bugs occurred. 
All but five per cent, of the vegetable food was derived from 
spores of fungi, very largely Cladosporium. Helminthosporium 
amounted to nine per cent. Macrosporium and Septoria were 
also found. Three per cent, of the spores of Physcia and other 
lichens, and two per cent, of the pollen of rag- weed and other 
Composite, complete the record. 
Four examples of H. converyens , all taken at Normal in 
August and September, had eaten about the same amount of 
animal food as the preceding species (forty per cent.), but differed 
in the distribution of it by the fact that one of the specimens had 
eaten a myriapod (Geophilus), and that a caterpillar had been 
taken by another. Insects proper amounted to but twenty-five 
per cent., over half plant-lice. The vegetable food of this species 
stands at fifty-six per cent., as compared with fifty-four of the 
preceding, and the ratios under this head are very similar to those 
just given for the other species. Pollen of Composite (dandelion) 
makes thirteen per cent, that of grass makes five per cent., spores 
of lichens two, and those of fungi thirty-three per cent. As in 
//. maculata , Helminthosporium was by far the most important 
