4 Ins. 
XIII. INSECTA. 
[1904] 
Verhoeff (1435) discusses the morphology of leg and of hypopharynx ; 
and in a postscript announces that morphologists have hitherto been in 
error as to the maxilla) of Insects ; the labium being really the anterior, 
not the posterior, of the pairs of maxillce. The same author gives an 
anatomical study (1434) of Emhiidce^ treating them as a suborder of 
Isoptera ; and he also amplifies his views as to the structure of the thorax 
in Hexapoda. Schaudinn (1224) in his work on the life-history of a 
parasitic Protozoon, gives an account of the alimentary system and of the 
mode of feeding of Culex pipie7i6. He inclines to the opinion that the 
poisonous effect of its bite is due to the enzyme of a commensal fungus. 
ViGiER (1456) informs us that he has discovered an apparatus of accom- 
modation in the eye of Aeschna for seeing at different distances. 
EossiG (1189) gives an interesting paper on the formation of galls of 
Cynipidoe, in the course of which he discusses the function of oenocytes. 
HouARD (719) contributes an extensive paper on the structure of galls; 
although predominantly botanical it treats of the determinants and is of 
considerable importance. 
Some works on development have already been mentioned, but there 
are numerous others. The study of cuticula and ecdysis is now being 
pursued, and we have from Plotnikow (1089) a valuable paper connected 
with the histology of the subject. Anglas (32) makes an important 
suggestion as to the relation of tracheae to metamorphosis. Bauer (93) 
enlarges on the extreme changes that take place post-embryonically in the 
central nervous system. 
Deegener (358) discusses the changes that take place in the mesenteric 
region, showing that there is a special pupal epithelium, acting functionally 
for the digestion or partial digestion of the "yellow- body." Powell (1104) 
gives information as to the formation of wings of Coleoptera etc. ; main- 
taining that wings are outgrowths of the pleuron or tergum, or both ; a 
conclusion which seems at present the only one consistent with all the 
evidence that has been obtained. Kellogg has experimented on larvae of 
Lepidoptera and confirms the previous observation of Oudemans that ex- 
tirpation of the sex glands does not afiect the development of the secondary 
sexual characters (781). In metamorphosis see also papers by Dewitz 
(377, 378) on the physiology thereof, including coloration and chitinisatiou, 
in which he is inclined to extend the importance of enzyme action. 
AsHMEAD has nearly or quite completed his classification of the Hymen- 
optera by a huge contribution (41) on the important group Chalcidioidea^ 
which he considers includes 14 families. R affray has published a general 
work on the Pselaphidte (1114), a family he has made of the first importance. 
It is a matter for regret that he has been obliged to defer the execution of 
a monograph for the present. De Meijere's paper on Conopida; (933) 
makes a large addition to our previously meagre knowledge of the biology 
of this curious family of parasitic Diptera. Baker (76) has given a 
catalogue of fleas complete to date, with information as to works and 
localities, and has revised the American forms. 
Amongst the remarkable events of the year must be placed the discovery 
in France of a new genus of blind Dytiscidce in a deep well fed by a 
subterranean spring, Abeille (3). This gives considerable support to 
the idea that Cave faunas have their origin in a hypogeal fauna of which we 
know little or nothing. An anomalous insect from the nest of a Termite 
has been described by Breddin & Borxer (173) and assigned to Rhynchota 
on somewhat unsatisfactory grounds. 
Among faunistic work we find the largest contribution in Meyrick's 
Australian Gelechiidce with 207 new species. He estimates the Australian 
Tineid?e at about 2,000 species — more probably an underestimate rather 
than the reverse. The publication in complete form of the results of the 
Harriman Alaska expedition is very w^elcome. The insects make two nice 
