1927 ] Notes on the Mite Pediculoides ventricosus Newport 161 
termined coleopterous larvae were observed. The mites in the 
white pine terminal shoots were, in general, most abundant 
directly under the bark where, in this damp situation, they 
probably feed upon dipterous larvae. 
A brief description of Pediculoides ventricosus may be useful. 
The males and unfed females are a pale straw color and measure 
l-5th mm. and less. The male remains slender, but the abdomen 
of the female swells enormously, assumes a spherical form, and 
attains a diameter of nearly 1 mm. Through the virtually trans- 
parent body wall of the abdomen, the contents, which are rather 
thin in consistency, appear the color of the yolk of a hen’s egg 
or lighter, with amorphous masses of a milky white substance 
throughout the yellow, though these are usually more or less 
localized. This amorphous white substance appears to be con- 
nected with the soft, rather globular eggs, which may be readily 
observed and counted. From two to thirty eggs have been 
observed in progressive stages of development, though Webster 
has counted forty to fifty. In mites that have been in dry sur- 
roundings, and perhaps in general, in the case of older mites, 
the yellow substance is thicker on one side of the abdomen and 
assumes a dark brown color. 
The life history of Pediculoides does not seem to have been 
completely worked out. Newport, who observed it in 1849, 
believed that the species was parthenogenic. Webster, in 1882, 
was inclined to agree with Newport, although he states later 
that he has noticed an occasional male. In this early paper, 
Webster says that the young not only hatch within the bladder- 
like abdomen but attain their full development there, and are 
liberated as they are developed. In breaking up the abdomen 
of the female, I have observed young mites crawling out of the 
fluid contents. Essig, in his text, “Insects of Western North 
America,” adds that Pediculoides mates soon after birth. Under 
favorable conditions they increase rapidly. When feeding, they 
crawl about upon a larva or a pupa, often puncturing the skin 
within a few minutes after discovering the prey, and then they 
more or less continuously suck the juices. It is interesting to 
note that the prepupae observed moved violently when a mite 
was placed upon them, but ceased the alternate curling and 
