ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 323 
honey from galls on a species of oak, Quercus undulata, growing on 
the young branches, and exuding, when young, copious drops of nectar. 
Prof. Eiley states that nectariferous galls are also produced on the 
hickory, Cary a porcina, by the attacks of a Phylloxera, the sweet juice 
probably resulting from the decomposition of tannin into gallic acid and 
sugar. The insect which produces the galls on the Quercus undulata is 
stated by Prof. Eiley to be an undescribed species, for which he pro- 
poses the name Cynips Quercus mellarise. Two Australian species of ant, 
Mellophorus Bagoti Lubb. and Camponotus inflatus Lubb., resemble the 
one above described in having the abdomen transformed into a honey-bag. 
Termites of Isthmus of Panama.* — Mr. P. H. Dudley has an account 
of his observations on the habits of the “ White Ants ” of the Isthmus 
of Panama ; the account of the battle of the white and yellow ants is 
particularly interesting, but the reader must refer to the original for 
details. 
S. Arachnida. 
Spinning Apparatus of Geometric Spiders.| — Mr. C. Warburton 
contributes some new facts to our knowledge of the spinning apparatus 
of geometric spiders. A spider’s line does not consist of many strands 
fused or woven together, but ordinarily of two or four distinct threads. 
The framework and the radii of circular snares are supplied by the 
arapullaceal glands. The acinate and pyriform glands are those which 
are mainly employed in binding up captured prey. The “ trailing line ” 
consists mainly of ampullaceal threads, some strengthened by others 
from the just-mentioned glands. The ground-line of the spiral is double 
only, and the two strands are bound together merely by the viscid matter 
which envelopes them. 
He corroborates the statements of Apstein that the “attachment- 
discs ” are furnished by the pyriform glands, that the tubuliform glands 
supply the silk for the egg-cocoon, that the viscid matter of the spiral is 
probably the product of the aggregate glands, and that, though the origin 
of the spiral ground-line is uncertain, it may proceed from the tubuliform 
orifices on the intermediate spinnerets. 
Protective Eesemblances in Spider s.J— Mrs. E. G. Peckham points 
out that there are, among Spiders, two forms of protective modification. 
The first includes all cases of protective resemblance to vegetable and 
inorganic things— that is, all modifications of colour or of colour and 
form that tend to make their possessors inconspicuous in their natural 
relations ; this she calls direct protection. Under indirect protection we 
have two classes : the spiders which are specially protected themselves, 
and those which mimic other creatures that are specially protected! 
Examples of the former of these two classes are afforded by spiders 
which become inedible through the acquisition of hard plates and sharp 
spines; and this modification of form is frequently accompanied by 
conspicuous colours, which warn their enemies that the spiders are 
unpalatable. 
* Trans. New York Acad. Sciences, viii. (1889) pp. 85-114. 
t Quart. Journ. Micr. Sci,, xxxi. (1890) pp. 29-39 (1 pi.). 
X Occasional Papers of the Natur. Hist. Soc. of Wisconsin, i. (1889) pp. 61-113 
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