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POPULAR SCIENCE REVIEW, 
Pholcus phalangioides of authors, and tlie only species of the 
genus indigenous to Britain. The female may be seen in 
summer with her ova grouped in a globular form under her 
sternum, in which situation they are sustained by the instru- 
mentality of the falces and palpi. 
The spider referred to by Mr. Jesse in his “ Scenes and Tales 
of Country Life/"’ pp. 202, 203, as being remarkable for the 
rapidity of its vibratory motions when disturbed, is undoubtedly 
Pholcus phalangioides, which, like Epeira diadema, Theridion 
quadripunctatum, and some other species, has the habit of 
violently agitating itself when anything suddenly touches 
its lines. This vibratory motion, which in the case of Pholcus 
phalangioides appears to acquire its maximum velocity, is 
produced by the partial contraction and extension of the joints 
of the legs in quick succession, as may be ascertained by 
occasioning specimens of this spider, or of Epeira diadema, to 
continue the action till it becomes so slow, in consequence of 
the fatigue experienced by the animals, that there is no diffi- 
culty in determining the manner in which it is effected. This 
singular proceeding is evidently intended by the spider to 
communicate motion to its snare, and thus to cause the 
struggles of any insect entangled in it, by which means it is 
directed with certainty to its victim. 
Family Linyphiidce. 
On the inferior surface of a small horizontal sheet of web, of 
a slight texture, constructed in corners of the windows of 
rooms that are unoccupied, or but little frequented, a small active 
spider may be seen to take its station in an inverted position, 
patiently waiting in that situation till some unfortunate fly or 
other minute insect suitable for food, shall become entangled 
in its snare. This spider, which, from the circumstance of its 
frequent occurrence in houses, has been named Linyphia 
domestica, is the Linyphia minuta of the “ History of the 
Spiders of Great Britain and Ireland,” and was originally de- 
scribed under that appellation in the “ London and Edinburgh 
Philosophical Magazine,” third series, vol. iii., p. 191. 
In September, the female fabricates several subglobose 
cocoons of white silk, of a loose texture, the largest of which 
measures about one-fifth of an inch in diameter, and contains 
from thirty to forty spherical eggs, of a yellowish- white colour. 
The cocoons are commonly attached to objects near the snare. 
Adult individuals of this species are liable to be infested by 
the larva of the Polysphincta carbonaria of Gravenhorst, an 
insect of the family Ichneumonidce, which feeds upon their 
fluids, and ultimately occasions their death. 
Another species of this genus, the handsome Linyphia crypt i- 
