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with Eupelmus piceus Riley, and Sarcophaga davidsonii, Coq. Of those collected at 
Redondo no less than 95 per cent were parasitized — 20 per cent with Sarcophaga and 
the remainder with Eupelmus. 
I failed to collect at such an early stage as to ascertain whether the parasite depos- 
its its eggs in those of the spider, or only among them ; but of this I am sure, after 
hatching they eat every egg they come in contact with, and if very numerous eat 
yolk, membrane, and all. I kept those till they hatched and found the average time 
of pupation was fifteen days ; some, however, have remained in the larval stage for 
more than a month, and may possibly remain so all winter. 
The number of Eupelmi contained in some of the cocoons seems unusual; of sev- 
enteen taken at random and counted one contained one hundred and eight and the 
total average was sixty-six. 
Of the Sarcophaga? a few hatched after ten days in the pupa stage; the others are 
either dead or awaiting the spring. The average number of Sarcophagi in each 
cocoon was three, but many of these proved abortive, as they in their turn were 
affected by a species of Tetrastichus, the cocoons being literally packed full of these 
little insects. I counted the contents of two of them ; they numbered fifty-six. 
Sarcophaga davidsonii I have also found in the cocoons of Phydippus oplfex, as has 
already been reported by Prof. Coquillett in Insect Life, and this season, though 
this spider is more abundant than heretofore, yet I find not more than 10 per cent 
of them affected and none with epiparasites. — [Anstruther Davidson, M. D., Cali- 
fornia, October 3, 1893. 
Abundance of the Red Spider in Illinois. 
Since this terrible drought, which more severely affected a certain section, 
including this vicinity, I have noticed tiees and shrubs, during hot winds from the 
southwest, with leaves suddenly turning as if burnt and falling off. Often alter- 
nate trees in a row are so affected. Sometimes the damage commences just above 
the lower clump of trees, goes right through upwards, and leaves the tree green 
below and above, especially northeast below and southwest above, but always 
beginning southwest. Today I observed a row of Sweet Pea vines similarly 
affected, regardless of constant watering, and soon I saw them covered with webs. 
I at once made my rounds, and found Cherry, Apple, Rose, Peach, Pear, Trumpet 
Creeper, Prickly Ash, etc., more or less affected in my own garden, and vegetation 
everywhere affected similarly. I give this as a sample and inclose affected leaves 
of Zanfhoxylum fraxinium, Cherry and Sweet Pea vines. The webs on Z. fraxinium 
(Prickly Ash) are most severe, as stems from the ground to the tip are coated. 
The Sweet Pea comes next, being affected from the ground up, but the tops of these 
trees are still green and in bloom. The Cherries, etc., are differently affected, some 
more and some less, the webs being mostly on the under side of the leaves and thick- 
est toward the wind, where the dust is filling the web and the latter is probably 
doubled over by the insect on that account. I also observed a large Apple tree with 
Trumpet Creeper running upwards on the southwest or windy side, literally cov- 
ered with this fine web between the creeper, the leaves of which are still green. 
A large Elm near by, also with a creeper upon it, is free from the webs, but the 
leaves of the creeper are somewhat affected. I notice that the little spider on 
Prickly Ash seems longer (more oval) and lighter in color than that on Cherry, the 
latter being more round and darker, resembling the spider, often- injurious to house 
plants in hot, dry, sunny rooms. In the hurry and short time of observation I 
noticed but one parasite which was seemingly feeding upon the spider. This was 
the larva of a Lace- wing Fly.— [A. H. Mundt, Illinois, September 5, 1893. 
Reply. — The leaves which you send are affected by a Red Spider of the genus 
Tetranychus, allied to but differing from the common Red Spider of the greenhouse 
(Tetranychus telarius). Its occurrence in your vicinity in such numbers is somewhat 
