REVIEWS. 22.5 
contribution to biological science is impossible without reproducing the 
whole paper, and to examine it critically needs much more than a super- 
ficial knowledge of the matter. One can only give a sketch of the 
contents and the manner of the treatment of the subject, with a state- 
ment of the conclusions to which the author comes as a result of his 
intensive study. We might say, in passing, that the assiduous collection 
of and search for aberrations, even those which appear at first to be 
trivial, and what is even more important still the recording of such in 
our current literature, has afforded the great bulk of material upon 
which this paper has been based. At the same time aberrations obtained 
_ by breeding are of as much, if not of more, assistance, since some of 
the proximal conditions, which may suggest direct or indirect factors 
in their production, are known. 
The author deals with the matter as follows :— 
OccuRRENCE oF GYNANDROMORPHISM. 
Structure and Classification. 
Reference is made to the more or less common occurrence of the 
phenomenon among insects compared with other animals, and in 
Lepidoptera it appears to be more common, probably because in all other 
orders of insects it is much less conspicuous. In the Hymenoptera only 
some 90 records were collected by Dalle Torre, while in an experiment 
with bees there were produced some hundreds of gynandromorphs. The 
various classifications which have been suggested are discussed, with an 
expression that ‘‘the more gynandromorphs one sees the more unsatis- 
factory does any attempt at classification by external characters appear 
to be.” The most elaborate classification on these characters is that of 
Dalle Torre and Friese who make four groups with a large number of 
subdivisions. The groups are.— 
Group I. Lateral Gynandromorphism. 
Group II. Transverse Gynandromorphism. 
(Dorso-ventral arrangement.) 
Group III. Frontal Gynandromorphism. 
(Antero-posterior arrangement.) 
Group IV. Mixed Gynandromorphism. 
(Lateral, transversal and frontal intermixed.) 
Nearly all gynandromorphs fall into Group IY. 
The writer regrets the small number of dissections which have been 
carried out, greatly hampering the classification based on internal 
structure, and puts forward the following 
I. Genetic HermapPHropitss. 
Primary sex glands of both sexes present. 
1. Lateral. 
a. Ovary on one side. Testis on the other. 
b, Two ovaries on one side. ‘Testis on the other. 
c. One ovary on one side. ‘Two testes on the other. 
d. Two ovaries on one side. Two testes on the other. 
2. Unilateral. 
Ovary or testis on one side. 
Ovary and testis on the other. 
3. Bilateral. 
Ovary and testis on both sides. 
