ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
335 
as a product excreted by protoplasm and solidified ; it is really a peri- 
pheral differentiation of this last in which certain parts of the general 
reticulated system are enclosed. 
0. Myriopoda. 
Developmental Stages of Julidae.* * * § — Dr. C. Yerlioeff finds what he 
lias called a Schaltstadium in the life-history of Julus italicus Latzel. 
This species has a flagellum which is absent in those other Julidae in 
which the author has observed a Schaltstadium , with a many-jointed 
first pair of legs. The possession of a well-developed flagellum is 
regarded as characteristic of the genus Julus, which the author separates 
from five genera previously included within it, and divides into nine sub- 
genera. 
Eyes of Scutigera coleoptrata.f — Dr. Th. Adensamer describes the 
minute structure of the eyes of this Myriopod, corroborating in great 
part the results previously reached by Grenacher. In external ap- 
pearance and in pigmentation the eye resembles that of Insects and 
Crustaceans. But while the crystalline cone in the latter is usually 
formed by the one-sided secretory modification of four cells whose nuclei 
persist, that of Scutigera is formed from five to seven cells whose cell- 
substance and nuclei are transformed into the crystalline body, which is 
surrounded by a persisting membrane. The crystalline cone of Insects 
and Crustaceans lies in front of the retinula ; that of Scutigera is en- 
veloped by the retinula. In the sensitive part of the ordinary facetted 
eye there are usually seven cells ; the retinula of Scutigera consists of 
two rows, the upper of nine to twelve cells, the lower of four or three. 
On account of these and other peculiarities, the author proposes to call 
this type of eye a “ pseudo-facetted eye.” 
S. Arachnida. 
Eyes of Harvesfmen.J — Dr. F. Purcell homologizes the two eyes oi 
Phalangids with the median eyes of Scorpions ; but the former have no 
central cell and no inter-retinular pigment-cells. The work is without 
any illustrations. 
Revival of Tardigrades.§ — The note by M. D. Lance on this subject 
does not state exactly to what extent “ dessication ” was carried ; only 
those Tardigrades revived after it which live in media that are alternately 
wet and dry. The drying must be slow, and when it is it is not followed 
by death but by slowing down of all the vital functions. The power of 
revival is due to adaptation to the conditions of the medium. 
Appendages of Pygidium of Triarthrus.]] — Mr. C. E. Beecher, con- 
tinuing his observations, states that the material lately worked out in the 
Yale Museum leaves little to be desired in the way of perfect preservation. 
* Zool. Anzeig., xvi. (1893) pp. 479-82. 
f Yerh. Zool. Bot. Gesell. Wien, xliii. (1893) pp. 573-8 (1 ph). 
t ‘Ueber den Bau der Phalangiden-Augen,’ Berlin, 1894. See Amer. Natur., 
xxviii. (1894) pp. 345 and 6. 
§ Comptes Rendus, cxviii. (1894) pp. 817 and 8. 
|| Amer. Journ. Sci., xlvii. (1894) pp. 298-300 (1 ph). 
