52 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
sufficiently exceptional to justify the creation of the new name hyper- 
metamorphoses. 
The classification of the Coleoptera has been primarily based on the 
form of the jaws, by which these animals may be divided into two series, 
according as they are adapted for animal or vegetable aliment. In the 
first series the agile larvae known as campodeeiform predominate, and the 
tarsi of the adult are nearly always pentamerous. In the second series 
the larvae are inactive or melolontlioid, and the tars^may be tetra-, penta-, 
or hetero-merous. In each series the families have been arranged 
according to the degrees of condensation of the abdomen and the coales- 
cence of the nervous ganglia. 
Morphology of Crustacean and Insect Appendages.* * * § — Dr. H. J. 
Hansen publishes a preliminary account of his prolonged studies on the 
homologies of Arthropod appendages. Among his chief conclusions are 
the following : — The occurrence of three joints in the basal piece of 
Crustaceans is the primitive state, still frequently persistent. The 
Malacostraca must be re-arranged, and the basis for this is to be found 
in part in the diverse structure of the thoracic limbs. In Thysanura 
and some Orthoptera there are four pairs of mouth-parts, homologous 
with those of Amphipods. There is a much closer agreement between 
the head of MacTiilis and that of Malacostraca than has been hitherto 
supposed. Hansen’s particular results, which differ in many respects 
from current opinions, are summed up in fifty-one conclusions, of which 
the above afford only a general indication. 
a. Insecta. 
Mimicry.f — Dr. C. Haase continues his elaborate discussion of 
mimicry in Lepidoptera and in Papilionidse in particular. The mimetic 
resemblances between Lepidoptera and other Lepidoptera, harmless 
beetles, stinging Hymenoptera, &c., are discussed, as well as mimicry in 
Diptera, Molluscs, Batrachians, Reptiles, Birds, and Mammals. 
The most general conclusion which the author draws is that the 
systematic relations of the Papilionidae confirm the theory of the origin 
of mimicry in the course of natural selection. 
Muscular Action in Bombyx.J — Dr. M. L. Patrizi has made a 
number of experiments on the contraction of muscles in the silkworm 
and silkmotb. They are rather physiological than zoological. The 
duration of the contractions, the temperature changes, the velocity of 
the muscle-wave, the condition of tetanus, the duration of a reflex move- 
ment, &c., are discussed. As to the movements of the wings, Dr. Patrizi 
notes that just-hatched females showed 21*8 revolutions per second, and 
similar males 27*4 revolutions, with a maximum and minimum of 40 
and 21*2. After interrupted copulation the number in the male was 
80*4 (max. 45*2, min. 21*7); after naturally completed copulation the 
number was 25 (max. 34*7, min. 14*1). 
Spermatozoa of Dytiscus.§ — Prof. L. Auerbach has some remarks 
on a note which Ballowitz recently published in regard to his (Auer- 
* Zool. Anzeig., xvi. (1893) pp. 193-8, 201-12. 
f Bibliotheca Zoologica (Leuckart and Chun), Heft 8, pp. 73-120 (14 pis.). 
X Atti R. Accad. Sci. Torino, xxviii. (1892-3) pp. 452-69 (16 tracings). 
§ Anat. Anzeig., viii. (1893) pp. 627-30. 
