182 . : General Notes. [ Feb. 
the nuclear threads running off from the ends of these pegnenn 
to the poles of the nuclear spindle, as shown at Fig. 6, f and 
These “ conjunctive threads,” as Fol calls them, arrange IMS 
selves in such a manner as to form a double hollow cone with a 
common base. The segments of the filament then pass out along 
the line of these threads and gather at the two poles of the 
spindle. Fig. 5, a,and Fig. 8, 4, show early stages of this kani 
formation, and Fig. 8, a, and Fig. 7, 6,a little later. The n 
cell-wall or “nuclear plate” is then formed, as shown in Fig. . 
c, across these threads at right angles and about midway between 
the two masses of filaments, the parts of each of which have 
now united and form a rounded mass, in appearance like the 
until it reaches across the cell from side to side and forms a 
complete cell-wall. All these sections are radial longitudinal 
ones.—L/mer Sanford. 
ENTOMOLOGY. 
Critical Remarks on the Literature of the Organ of Smell 
in Arthropods.—[ The following abstract of the more important 
portions of Kraepelin’s criticisms on the works of writers on 
the olfactory organs of arthropods, may prove not unwelcome to 
‘our entomologists, who may never be able to obtain Kraepelin’s 
rather rare pamphlet. See pp. 889 and 973 of vol. xx—A. S. 
Packard. in 
My own observations on different groups of insects agree, in 
general, with those of. Perris, Forel, and Hauser, without being 
in a position to confirm or deny the varying relations of the 
Hemiptera. That irritating odorous substances (chloroform, 
acetic acid) cause the limbs to move in sympathy with the 
stimulus, I have seen several times in Acanthosoma; still it may 
be a Sees rather than olfactory stimulus. 
As regards Crustacea, there are no observations or experiments 
_ (except on Asellus) on the conjectural seat of their olfactory 
organs. It should be here mentioned that Jourdain has described 
and Professor Dohrn, in Naples, has reported to me that the 
Brachyura by a remarkable. movement of their inner antenne, 
which are almost continually in convulsive movements, seem to 
support the opinion long entertained of the perception of odors 
_ by the antenne 
oe 5 o spiders, it is not certainly known whether and to what 
they oes in the sense of smell. Robineau-Desvoidy 
cot said t hat their sense of smell is very well developed and 
paragre m the mandibles, but Perris placed them in the lowest 
hr ki i ei e remarks on “the sensibility of 
Turning n now w from peas and panpe observation to exact ; 
