178 General Notes. 
reappear. Experience has shown that the second is the condition 
which it obtains ; a normal leaf modified by the gall-forming material 
grew into a normal leaf, and a root into a root. 
“ The galls of Nematus are possessed of extraordinary vitality ; 
those of N. capree are found living long after the leaf is dead; N. 
viminalis, which is found on Salix purpurea, exhibits really remark- 
able properties ; although abandoned by their inhabitants at the 
beginning of autumn and being surrounded by damp mould during 
the winter, they not only remain perfectly turgescent, but some of 
them are able, in the following summer, to begin a new life. Galls 
cannot be inherited. The specific material secreted by Nematus 
capree—and what is true of it is probably true of other forms—is 
an albuminoid substance which acts as an enzymatic body.” 
HOMOLOGUES OF ARACHNID APPENDAGES.'—Herr A. Lendl 
has studied the development of Epeira diademata with reference to 
the much-discussed problem of the homologies of the appendages. 
The general conclusions of his investigations are as follows: (a) 
bes first pair of appendages represent antenne ; this is suggested by 
eir origin, position, motion, jointing, and innervation from the 
supra-cesophageal ganglion. (b) The small tubercles under the 
upper lip resemble mandibles in their origin and in the connection 
of their ganglia with the cesophageal ring. They appear more like 
mandibles in the embryo than in the adult. (c) The homology of 
an 188 the second nd pair of u i in insects.—Jour. H Mae. 
SYNOPSIS OF THE APHIDID& OF MINNESOTA.—Bulletin No. 4 of 
the Geographical and Natural History Survey of Minnesota is a syn- 
opsis of the Aphididee of that State, b Professor O. W. Oestlund, of 
the University of Minnesota. In this synopsis there is included a 
careful account of all the species of plant-life found in that State, 
together with notes on their habits. Many new species are described, 
and one new genus. The American species not yet found in Min- 
nesota are indicated ; and there is given a “ List of North American 
plants with the species of Aphides known to attack them.” 
Aw UNPUBLISHED ILLUSTRATED WORK ON NORTH AMERICAN 
ee —Dr. Hagen calls attention ? to “An unknown or for- 
1 Math. v. Naturw. Ber. aus Ungarn, ae bad pp. 95-100. 
ae ily Americana, vol. III, p. 1 
* 
