116 Recent Literature. [ February, 
to which all organisms are subjected, by producing both pollen 
and seeds. With respect to the plants belonging to the gyno-di- 
cecious sub-class, or those which co-exist as hermaphrodites and 
females, it has been proved that they yield a much larger supply 
of seed than they would have done if they had all remained her- 
maphrodites ; and we may feel sure from the large number of seeds 
_ produced by many plants that such production is often necessary 
or advantageous. It is therefore probable that the two forms in this 
sub-class have been separated or developed for this special end. 
Various hermaphrodite plants have become heterostyled, and 
now exist under two or three forms; and we may confidently be- 
lieve that this has been effected in order that cross-fertilization 
should be assured. For the full and legitimate fertilization of 
these plants pollen from the one form must be applied to the 
stigma of another. If the sexual elements belonging to the same 
form are united the union is an illegitimate one and more or less 
sterile. With dimorphic species two illegitimate unions, and with _ 
trimorphic species twelve are possible. Thereis reason to believe 
that the sterility of these unions has not been specially acquired, 
but follows as an incidental result from the sexual elements of the 
two or three forms having been adapted to act on one another in 
a particular manner, so that any other kind of union is inefficient, 
like that between distinct species. - Another and still more remark- 
able incidental result is that the seedlings from an illegitimate 
union are often dwarfed and more or less or completely barren, 
like hybrids from the union of two widely distinct species.” 
Breum’s Animat Lire—We have already (Vol. xi. p. 557) in 
general terms called attention to the elaborate and useful work of 
which the present volume forms a part. Prof. Taschenberg, the au- 
thor of this volume, is well known for his studies on the lower Hy- 
menoptera and his work on economic entomology. He brings to 
the task ripe scholarship, a pleasant style, and is aided by an artist 
whose success greatly enhances the value of the work. Ina few 
introductory pages, Prof. Taschenberg treats of the anatomy, 
physiology, and transformations of insects, and then enters at once 
_ upon a very general description of the more interesting forms of 
the families of insects, beginning with the beetles and ending with 
the myriopods, spiders and mites. The Linguatulide, and Panto- 
poda (Pycnogonidz) are included, and the Tardigrades are briefly _ 
noticed, 
The work is well worth the cost to one even who cannot read 
German with facility, from the graphic, full-page illustrations, ang — 
the cuts which abound in the text. The picture of the dead and — 
probably stinking mole hanging by its snare, and overrun with 4 — 
1 Brehm’s Thierleben. Bando. Die Insekten, Tausenfiissler und Spinner. Von — 
Dr. E. L. TascHENBERG. Mit 227 Abbildungen im Text und 21 Tafeln, von Emil 
© Schmidt. Leipzig, 1877. New York, B. Westerman & Co. New York. 8vo. 
So. Pps FIL, ex, a a 
