NOTES. ' [107] 



Too small in body to followtbehabitsof the other spiders -with the slightest chances 

 of snccess, nature has gifted this little heroine with a highly developed intellect by 

 which she is enabled to come victorious out of the so uneven tight, for the larva is often 

 fc-wenty to thirty fold larger and heavier. 



Let us look upon a larva, about half an inch long, feeding, unsuspecting the ap- 

 proaching danger, on the succulent leaf of the cotton plant. Suddenly we see a small 

 black dot not much larger than the head of a pin lowering itself from a leaf above to 

 that on which our larva feeds. This little dot is the Theridula, and, alighting on the 

 leaf, she runs busily backward and forward about the sluggish larva, always avoid- 

 ing to touch and disturb the larva, often climbing on a thread from one side to the 

 other side, thus surrounding the victim with a nearly invisible system of threads, tire- 

 less, adding strength to it, testing here, with all her force, the durability of one cord, 

 adding there another loop to a weak point. After an hour or more she has finished 

 her work, and suddenly disappears to the underside of the leaf above. Now the larva 

 becomes restless, it throws its head angrily about, its whole body jerks wildly, it 

 endeavors to walk away, but in vain ; it is held by invisible powers ; nay, it is lifted 

 ap from the leaf and gradually and noiselessly is hoisted to the underside of the leaf 

 above. It is wonderfulwhat strength and what amount of mechanical ingenuity are 

 here displayed. [Of the mechanism of this hoisting an often twenty times heavier 

 weight by the spider we know little, as the threads are very thin and the spider always 

 at the underside of a narrow projection , a crevice of a fence rail or stone, or the under- 

 side of a leaf, and being very shy, immediately interrupts her work at the slightest 

 disturbance. According to my notes it took a Theridula one hundred minutes to lift a 

 larva, over half an inch in length,- 6^ inches to the underside of the plate of my work- 

 ing table.] 



Having her prey, which has become exhausted and motionless by its fruitless en- 

 deavors to free itself, securely fastened to a projecting vein of the leaf, our little hero- 

 ine now throws out by her hind feet a mass of threads which she fastens over the larva 

 at the same time. Slowly and at long intervals does the larva move in its ties while the 

 little spider runs busily about it, fastening it with more ropes to the leaf; this takes 

 another hour, and now she cautiously approaches the larva, and after repeated trials 

 she has selected the right spot, generally at the second or third segment, into which 

 she introduces her poisonous fangs. Hours afterward we can see the victress motion- 

 less in the same position, sipping the sweet juice from the body of her victim. 



The following facts concerning one of the commoner spiders ( Oxyopes viridans) were 

 published by jVIt. Hubbard in the American Entomologist, vol. iii, p. 250 : 



August 28, 1880. — In the field to-day I observed a spider, Oxyopes viridans, eating a 

 Tachinid (T) fly. These large green spiders are quite common. I am inclined to think 

 they do not attack the caterpillar. I watched one resting upon the same leaf with a 

 worm, to which the spider paid no attention. During the entire morning the spider 

 remained upon the same leaf, while the caterpillar wandered to the next leaf, and fed 

 in plain sight of the spider unmolested. Another specimen of the same spider ran 

 over a leaf, on the underside of which a caterpillar was feeding. The caterpillar 

 jerked and shook the leaf, but the spider paid no attention to it. 



September 3. — This morning I could not find a caterpillar in the ''Simpson, cotton," 

 excepting one just hatched. I saw the green Oxyopes feeding upon a bee, Anthophora 

 or Megachile, or some bee of medium size. (I did not succeed in securing it.) There 

 are many burrows of a Cieindela larva (probably C. punctulata, which is abundant in 

 the cotton fields). They (the larvae) capture ants chiefly. 



Note 29 (p. 102). — Trichogramma pretiosa Eiley {Can, JEnt., vol. xi, p. 161.) — 

 Length about 0.3"^™, yellow, the eyes red, the wings hyaline. Head wider than the 

 thorax ; aptennaB 5 jointed, joints 3 and 4 in the $ forming an ovate mass, and together 

 shorter than joint 2 ; joint 5 large, thickened, and very obliquely truncate ; in the ^ 

 joints 3, 4, and 5 form a more or less distinct elongate club, beset with long bristles^ 

 Hairs of the wings arranged in about fifteen lines. Abdomen not so wide as the 

 thorax, but as long as the head and thorax together ; in the 9 the sides subparallel 

 and the apical joint suddenly narrowed to a point. 



Difl'ftrs from Tricliogramma niinuta Eiley (Third Rep. Ins. Mo., p. 158, fig. 72, $ ) in 

 its smaller size and uniform pale yellow color, and also in the form of the third and 

 fourth joints of the antennse. 



Note 29a (p. 104). — This species, although so much resembling the Trichogramma 

 egg parasite, belongs to the family Proctotrupidae, subfamily Mymarinas. We have 

 erected for it, provisionally, the MS. genus Metamymar, and have given it the specific 

 name of aleurodis. 



