202 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
times instead of gemmation there occurs what may be called a secretory 
segmentation, the autcrior portion of the cell being divided off and the 
contents extruded through an aperture in the wall. 
Autotomy in Grasshoppers.* * * § — Dr. F. Werner finds that Ephippigera 
vitium, Earbitistes serricauda, Saga serrata, and occasionally Locusta 
viridissima, amputate their limbs. When Earbitistes serratus is captured 
it bites off its anterior legs by the root ; when the others are kept in 
captivity they proceed to eat oft’ the tarsi or even as much as half of 
their appendages. In the case of Mantis a destruction of the tarsi was 
noticed, but the herbivorous Acridiid® and Gryllodidte are not known 
to exhibit this strange freak. 
Spirally-coiled Cases of Insect Larvae, t — Dr. E. von Martens dis- 
cusses the resemblance between Cochlophora valvata and the Gastropod 
Valvata. His specimens were collected by Stulilmann on his journey 
with Emin Pasha, and no species of Valvata occurs in the region where 
they were found. Moreover the Cochlophora measured 10-11 mm. in 
height by 11-12 in breadth, and had three or four coils, while no 
species of Valvata even half as large is known. The habitat of the 
Gastropod is in water, that of the insect larvae on dry land. There 
is no mimetic relation between the two. The spiral coiling of the 
insect’s case is a convenient independent adaptation. 
In Stuhlmann’s collection twenty specimens were coiled to the right, 
and twenty-two to the left. It is of interest therefore to inquire into 
the direction of the spiral in similar insect larvae. Yon Martens finds 
that in thirty-one specimens (or records) of Psyche or Cochlophora helix, 
not one was coiled to the right ; that Psyche Planorbis is also coiled to the 
left ; and that in numerous forms of aquatic origin (Phryganidae) all but 
one were coiled to the right. The East African spiral cases are remark- 
able in having a homogeneous texture. Finally von Martens refers to 
that Phryganid case which Lamarck called Dentalium nigrum, and to 
Paludina lustrica Say, Dentalium ccrneum L., and I), pellucidum Gmel., 
which are sometimes ranked as cases of insects, but which are not, the 
first being a Gastropod, the others tubes of Annelids. 
S. Arachnida. 
Protective Colour of Spiders. Herr M. Bartels describes the pro- 
tective nature of the colour in Epeira diademata (yellowish-grey, orange- 
yellow, orange-red) as observed in forms living among juniper bushes. 
“ The coloured abdomen was scarcely distinguishable from the yellowish- 
red twigs,” and so on. He also notices that the startled spiders seek 
safety by dropping from the branch on to the ground. 
€. Crustacea. 
Crustacean Blood-corpuscles.§ — Mr. W. B. Hardy gives an account 
of the blood-corpuscles of Astacus and Daphnia. In a drop of blood 
taken from a well-fed Astacus, a large number of actively amoeboid 
* Zool. Anzeig., xv. (1892) pp. 58-60. 
t SB. Gesell. Nat. Freunde Berlin (1891) pp. 79-85. 
f Torn, cit., pp. 1-4. 
§ Journal of Physiology, xiii. (1892) pp. 165-90 (1 pi.). 
