QUARTERLY CHRONICLE. 213 
searches on the retina by the illustrious editor. The papers 
are as follow: 
1. “ Epithelial and Gland-cells,” by Franz Eilhard Schulze. 
2. “ On Secreting-cells in the Integument of Limaz,”’ by 
Max Schultze. 
3. “ On Hyalonema,”’ by Max Schultze. 
4. “On the Rods and Cones of the Retina,’ by Max 
Schultze. 
5. * On a Theory of Colour-perception,” by Dr. W. Zenker. 
6. ‘‘ On the Peripheral Ending of Motor Nerves,” by Dr. 
W. Moxon. 
The paper by Herr Franz Schulze appears to be a very 
elaborate and detailed essay on the epithelial cells of Fishes, 
Amphibia, Reptiles, and Mammalia, and the plates are very 
beautifully executed. We cannot, however, here give his 
results, as they are spread widely over the whole paper. 
Prof. Schultze’s paper on Limaz is a short description, 
called forth by the preceding paper, of the gland-cells in the 
slug, which secrete the enormous quantity of mucous matter 
noticeable in these molluscs. 
Dr. Pietro Marchi, of Florence, who has been making ob- 
servations on this structure, is investigating its homologue in 
other snails, and will publish a paper on the subject shortly. 
Prof. Schultze’s paper on Hyalonema is a translation of 
that which he recently published in English, in the ‘ Annals 
and Magazine of Natural History,’ and which we have pre- 
viously noticed. 
Dr. Zenker’s paper is one dealing with optical and phy- 
sical laws, as wellas with anatomical structure. He discusses 
the relation of the wave-lengths of light of various colours 
to the perception of colour, and gives as his chief result 
that this sense is not so much to be regarded as dependent 
on the time of vibration of the light, as on the position of the 
incident rays in relation to the elements of the retina. 
The number concludes with a brief abstract of Dr. Moxon’s 
paper, published in the January number of our Journal. 
FRANCE.—Annales des Sciences Naturelles.—‘* The Re- 
production of Aphides.’’ In our Chronicle of October, 1866, 
we noticed Dr. Balbiani’s paper “‘ On the Reproduction of 
Aphides,”’ in which he maintained their hermaphroditism, 
and described a hitherto unrecognised “ testis.” During the 
same period Herr Mecznikow, a most brilliant and trust- 
worthy observer, was studying the reproduction and deve- 
lopment of Aphis, and has published his conclusions in 
the ‘ Zeitschrift,’ which are very similar to those of Huxley, 
excepting that he regards a green mass developed in the 
