356 FRESH FACTS [NovEMBER 1899 
near the water’s edge, reached out and caught hold of the tip of an overhanging 
leaf, and climbed into it. With their hind legs both male and female held the 
edges of the leaf, near the tip, together, while the female poured her eggs into 
the funnel, the male fertilising them as they passed. The jelly in which the 
eggs were laid was of sufficient firmness to hold the edges of the leaf together. 
Then moving up a little further more eggs were laid in the same manner, the 
edges of the leaf being sealed together by the hind legs, and so on up the leaf 
until it was full. As a rule two briar leaves were filled in this way, each 
containing about 100 eggs.” Even more interesting, however, is the subsequent 
development. 
How Correpops Swim! E. W. Macsripe. ‘The movements of Cope- 
poda,” Quart. Journ. Mier. Sci. xlii. 1899, pp. 505-507. In the freshwater 
Cyclops the first antennae assist in the slow movements, and the belief is 
general that copepods propel themselves by their first pair of appendages. 
Prof. Macbride observed at Plymouth that the slow gliding movements of 
marine copepods are effected principally by the second antennae, the gnathites 
likewise assisting, notably the second maxillae. The quick movements,fon the 
other hand, are effected entirely by the simultaneous action of the thoracic 
feet. 
Cuamps in Anmmats. Orro Turto. ‘Sperrvorrichtungen im Tierreiche,” ” 
Biol. Centralbl. xix. 1899, pp. 504-517, 13 figs. Dr. Thilo points out that one 
must serve some apprenticeship in engineering before one understands the 
animal body, and his ingenious essay bears this out. He leads us from the 
valves of the heart to the device which keeps the globe-fish’s self-inflation 
from collapsing, but he is at his best in expounding clamps for rigid structures. 
From the clamp of the spine of Monacanthus (a fish from the Red Sea coral- 
reefs), we pass to more complex cases in 7’riacanthus and the stickleback, and 
the leverage-system which works the snake’s fang is not forgotten. It is an 
essay for a dull afternoon, so ingenious is it; but it is with some misgivings 
that we are forced to conclude that in addition to mathematics and meteorology, 
statistics and spectroscopy, psychology and philosophy, and much more, the 
complete naturalist must also learn engineering. 
VARIATIONS IN JELLYFISH. E. Batiowrrz. ‘Ueber Hypomerie und 
Hypermerie bei Aurelia aurita, Lam.,” Arch. Entwickelungsmechantk, viii. 1899, 
pp. 239-253, 1 pl. This common jellyfish seems to be ai animal well deserving 
the attention of those who follow the modern statistical method of the study 
of variations. It is normally a tetra-partite creature, but sex-partite, pent- 
partite, and, more rarely, tri-partite forms may be found thrown up on the 
beach. Sometimes the variation is very consistent throughout; thus a tri- 
partite individual had a three-cornered mouth, three genital pockets, six 
marginal bodies, etc. ; but, often, there is less uniformity and transitional forms 
occur. Some of the variations may be traceable to the Ephyra-stage, but most, 
according to Ballowitz, must have an earlier origin. Here is evidently a case 
for experiment to assist observation. 
DIGESTION IN FisHes. Emite Yune. ‘Recherches sur la digestion des 
poissons (Histologie et physiologie de l’intestin”), Arch. zool. expér. vii. 1899, 
pp. 121-201, 1 pl. Prof. Yung has made many histological observations and 
physiological experiments in regard to digestion in fishes, and has removed 
some of the prevalent vagueness. The formation of pepsin seems rigidly con- 
fined to the stomach-sac and to a particular region of it. 
Tue Propiem or Equitipration. Tx. Beer.  “ Vergleichend - physio- 
logische Studien zur Statocystenfunction. ii. Versuche an Crustaceen (Penaeus 
membranaceus),” Pfliiger’s Arch. f. Physiol. \xxiv. 1899, pp. 364-382. When 
the statocysts of Penaeus are extirpated, the animal can no longer keep its 
balance in swimming ; it falls to one side or to the bottom. 

