Miscellaneous. 183 
tasteful retreat was thus obtained at the only really available spot 
in the vicinity of the snare. 
7. When the furrow-spider weaves her orb upon the exposed 
surfaces of human habitations, as the cornices of porches, outhouses, 
&c., her nest takes a form quite different from any of the above. 
A tube of stiff silken fibre) is spun against the surface, to which it is 
lashed at all sides. This cylinder is about an inch long and half an 
inch thick, and, at the end towards the orb, has a circular opening 
about a quarter of an inch in diameter. The stiff texture of the 
nest appears to be necessary to make the walls self-supporting, in- 
asmuch as there are no supporters like the twigs and leaves found 
at hand in arboreal sites. Moreover the open position of the domi- 
cile exposes the spider very freely to the assaults of the mud- 
daubers who frequent such localities, to birds, and other enemies ; so 
that a canvas is needed of tougher texture than that required in 
sheltered sites. It may be remarked that in old buildings, which 
present cracks and crannies convenient for nesting, woven nests of 
this sort will rarely be found. 
It is thus seen that while there is a general regard to protection 
of the spider’s person, there is a modification over a quite wide 
degree of variation in the form of the protective nest; further, 
that this modification appears to be regulated, more or less, by the 
accidental environment of the domicile, and in such wise as to 
show no small degree of intelligence in adapting the ordinary spin- 
ning habit to various circumstances, and to economizing labour and 
material. Proc. Acad. Nat. Sci. Philad. March 21, 1882, p. 97. 
On Segmentation in the Mites. By P. Krammr. 
After referring to some previous publications of his own and of 
other writers on this subject, the author describes, as follows, the 
segmentation of a minute mite found by him on the ground in a fir- 
plantation in the Thiringer Wald, and which he identifies with 
Alycus roseus of Koch. He says :— 
“The dorsal aspect shows a very distinct segmental line between 
thorax and abdomen. The shoulders of the latter project rather 
convexly ; and between them the segmental line is slightly sinuated 
posteriorly. The abdomen shows nine distinct segments, which 
follow one another exactly as we see them in the little Podure. The 
segmental grooves between the first three abdominal segments are 
broad, and present, to a certain extent, the appearance of double 
lines, of which the anterior cut off the preceding segment, and the 
posterior commence the succeeding one. The lateral margin of the 
abdomen shows distinctly the convexities and constrictions which 
correspond to the middles and the boundaries of the segments. 
The setation throughout follows the segmental conditions ; there 
are rows of setz upon the surfaces of the segments, only running 
parallel to the boundary-lines of the segments. The hindmost 
segment bears the perfectly terminal anal aperture, half of which 
is seen in the dorsal view, while the other half is seen in the ventral 
aspect. 
“On the thorax there is a distinct pair of eyes, furnished with 
