19G 
MOLLUSCOIDA. 
communicated to the R. Accademia dei Lincei at Rome, Feb. 1, 1874, 
have not been seen by the Recorder. 
APP£NDICULAEIIDJi3. 
E. Ray Lank ester’s observations on the development of the heart 
[Zool. Rcc. X. p. 181] are fully given aud illustrated in Q. J. 
Micr. Sci. xiv. pp. 274-277, pi. xii. A new genus described by H. Fol, 
Arch. Z. exp^r. iii. p. xlix. 
POLYZOA. 
Korotnieff has observed and minutely described in a species of 
Paludicella : — 1. The gemmation or budding of the zooecium, which he 
regards as the sexual individual, formed by three primary layers, viz., 
endocyst, ectocyst, and external chitinous stratum : the budding itself 
begins by inward folding of the wall of a terminal zooecium, which 
finally reaches the opposite wall, and so forms a new individual ; a 
similar process occurs also on the lateral wall of other zooecia. 2. The 
budding of the polypid, which he regards as a nourishing individual : 
this begins by exuberant pullulation of the cells of the endocyst, and 
soon assumes the form of an ellipsoid, lying parallel with the longi- 
tudinal diameter of the zooecium ; the oesophagus, middle intestine, and 
rectum make their first appearance as distinct cavities, separated by 
transverse septa ; two primitive strata of cells are distinguishable in this 
bud, the inner one giving origin to the lophophore and nervous system, 
the outer to the muscular system and intestine, and both participate 
in the formation of the oesophagus ; the greasy bodies are not excreta, 
but pabulum. 3. The decaying of the polypid. Nachr. Ges. Mosc. x. 
pt. 2. 
W. Salensky gives notes on the budding of the marine Polyzoa. He 
states that every bud of a polypid consists of two strata, the inner com- 
posed of several layers of globular cells, the outer of one layer of 
flat spindle-shaped cells, the former giving origin to the tentacular 
sheath, and outer epithelium of the intestine, the latter to the inner 
epithelium of the same ; the ovaries are homologous to the polypi ds, 
as thought by Allman. Z. wiss. Zool. xxii. pp. 343-348, pi. xxxii. 
figs. 1-3. 
H. Nitsciie confirms, from his own observation, the somewhat strange 
fact, first observed by Metschnikoff, that in the fresh- water Polyzoa^ 
especially in the genus Alcyonella, the polypid is formed by a fold of 
the skin of the cystid, which is directed inwards, the outer epithelium 
of the cystid or ectoderm forming the inner layers, and the inner 
epithelium or entoderm the outer layers of the young polypid. 
Both layers take part in the formation of the intestine, as well as of 
the lophophore of the polypid. SB. Ges. Leipzig, i. pp. 31-36. Some- 
thing like the shell-gland of young Mollusca is stated to exist in Loxo- 
soma ; E. R. Lancaster, Q. J. Micr. Sci. xiv. p. 390. 
