ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
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species the edge of the sole is sensitive, but in many experiments it 
exhibited no sensibility at all. The neighbourhood of the mouth was 
likewise found to be insensitive. The tentacles are universal sense- 
organs, as they exhibit all possible activities of sense. None of the 
species examined appeared to be sensitive to sound, and most were also 
insensitive to light. 
Alicia.* — Mr. J. E. Duerden has made an anatomical investigation 
of this genus cf sea anemones, and comes to the conclusion that it is 
necessary to form for it a new family which may be defined as con- 
sisting of Hexactiniae with a large flat contractile base, with simple 
cylindrical tentacles. The column provided with simple or complex 
hollow processes or vesicles over the greater part of its surface, arranged 
mostly in vertical rows. No cinclides. The sphincter muscle endc- 
dermal and diffuse, varying in the extent of its development. Perfect 
mesenteries few or numerous. No acontia. Owing to our ignorance 
of the anatomical condition of many of the sea anemones, he thinks it 
premature to discuss the position of his new family. 
Variation of Tentaculocysts of Aurelia aurita.f — Mr. E. T. Browne, 
on the suggestion of Prof. Weldon, has examined a large number of 
specimens of the Ephyra and adult stage of Aurelia aurita, for the 
purpose of finding out the variation in the number of tentaculocysts ; 
and, if the variation occurred among the Ephyrae, to see how far it 
affected the adults. Of 359 Ephyrae collected in 1893 no less than 81, 
or 22-6 per cent., are abnormal in possessing more or less than 8 
tentaculocysts, and the range of variation extends from 6 to 13 tentacu- 
locysts. The percentage of abnormal specimens presented by the 
1156 Ephyrae collected in 1894 tells much the same tale. Of 383 
adult Aurelise collected in 1894, 87 specimens, or 22*8 per cent., have 
a variation in the number of tentaculocysts. The variation, on the 
whole, shows a tendency for an increase in the tentaculocysts. Whether 
this will change the present characteristic features of the species or not 
can only be found out by examining the Ephyrae and adults at long 
intervals of time, and comparing the results with previous records. 
Development of Scyphomedusae.f — Miss Ida H. Hyde has investi- 
gated the early stages in the development of several Medusae. In 
Aurelia flavidula the germ-layers are formed in two different ways : 
eggs from Eastport, Maine, give rise to the endoderm by a process of 
delamination, combined with inwandering of cells from various parts of 
the blastula wall ; eggs from Annisquam formed invaginate gastrulas. 
In Cyanea arctica the gastrulation is a modified invagination in which 
some cells break loose from the pole that is invaginating ; there is, 
however, no trace of the multipolar inwandering of cells described by 
McMurrich. In all the species examined the mouth is a new formation, 
and not a reopening of a gastrula mouth. The inrolled part of the 
ectoderm remains as the oesophagus. The first pair of gastric pouches 
arise as a pair of outgrowths from the endoderm, but the second pair 
comes from the ectoderm. It is thought that these observations 
* Ann. and Mag. Nat. Hist., xv. (1895) pp. 213-8 (1 pi.). 
f Quart. Journ. Micr. Sci., xxxvii. (1895) pp. 245-51 (1 pi.). 
% Amer. Natural., xxix. (1895) pp. 289-90. 
