ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
625 
Wright’s Nausitoria , possibly Gould’s Lyrodus , and species referred to 
other genera. The new species described is distinguished by the 
rounded and produced auricle of the valve, and by the liatchet-shaped 
palettes. 
Arthropoda. 
Phytogeny of Pantopoda.* — J. E. W. Ihle discusses the various 
opinions held as to the relationships and phytogeny of the Pantopoda. 
He holds that it is impossible to ally them with Arachnoids or with 
Crustaceans, but he thinks that the Myriopods may be regarded as the 
ancestral stock. The Pantopoda should be ranked as an independent 
class of Tracheata, very divergent, but more nearly related to Myriopoda 
than to any others. The occurrence of a pair of abdominal appendages 
is especially emphasised. 
More ‘Challenger’ Pycnogonids. t — Dr. P. P. C. Hoek describes 
four new species of Pycnogonids, — Pallene dimorpha , Anoplodactylus neg- 
leda , Colossendeis japonica , and Pycnogonum magellanicum. They were 
found by Prof. G. 0. Sars in his £ Challenger ’ collection of Cumacea, 
after the completion of the report on Pycnogonids. The author also 
describes GhsetonympJion hirtum Kroyer from the southern part of the 
North Sea. 
a. Insecta. 
Individual Variation in Wings of Lepidoptera.J — Mr. W. L. W. 
Field has tried to answer two questions in this connection : — (1) Is a part, 
developed in any given species in an extraordinary manner as compared 
with the development of the corresponding part in other allied species, 
more variable than parts which exhibit less specific peculiarity ? and (2) 
Which sex is the more variable ? He worked with the moth Thyreus 
abbotii Swainson, one of the common Sphingidge of Eastern North 
America, and his measurements related to the irregular and very long 
outer margin of the wing. He finds that this, the most aberrant dimen- 
sion of the fore-wing, is likewise the most variable. This accords with 
Darwin’s law. The females show, in general, a greater degree of varia- 
bility than the males; but in the markedly aberrant feature under 
discussion, their variability is less than that of the males. It is possible 
that the sinuosity of the margin has a protective significance, and is of 
less importance in the males whose conditions of life are easier. 
Natural Selection in Lepidoptera.§ — Mr. M. L. Sykes illustrates 
this by a study of mimicry, and gives an admirable exposition illustrated 
by eight photographed plates. 
Post-embryonic Development in Ants.|| — Herr W. Karawaiew now 
publishes full details of his investigations on this subject in Lasius 
flavus. As to method, the author chiefly emphasises the necessity for 
dropping the larvm for a few seconds into water heated to about 80° C. 
before fixation. The fixing agents, of which several were tried, were then 
used cold. The most important general result is to show that, in marked 
* Biol. Centralbl., xviii. (1898) pp. 603-9. 
f Tijdschr. Nederl. Dierk. Ver., v. (1898) p. 290 (2 pis.). 
% Proc. Amer. Acad. Sci., xxxiii. (1898) pp. 389-96 (5 figs.). 
§ Trans. Manchester Micr. Soc. for 1897 (issued 189S), pp. 51-61 (8 pis.). 
|| Zeitschr. f. wiss. Zool.. lxiv. (1898) pp. 385-178 (1 pis. and 15 figs.). 
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