HYDROZOA. 469 
On a few Zoophytes from Mozambique, ef. Bianconi, Mem. Ac. Bologn. ix. 
pp. 211-214. 
E. van Beneden uses weak’ osmic acid to preserve Medusce and Ctenoplioraf 
and concentrated solution of picric acid for small Medusce {Oceania) and 
Noctilucce. Ann. Sc. Nat. (5) xv. no. 9, pp. 2 j Bull. Ac. Belg. xxxii. 
pp. 179-181. 
Schulze & Wittich preserve Hydra}, Medusce, &c. by allowing them to 
expand perfectly, and then adding a quantity of osmic acid suddenly to the 
water, which kills them before they have time to close. They must be taken 
out immediately, washed with distilled water, slightly tinted with carmine, 
and then preserved in spirit of 62°. Rostocker Tageblatt, 1871, p. 63 j cf. 
Z. ges. Naturw. (2) iv. pp. 282 & 283. 
Glass models of Coelenterata &c., made by Blaschke, of Dresden, are men- 
tioned by Troschel, SB. Ver. Rheinl. xxviii. p. 78. 
HYDROZOA. 
Hydroida. 
E. J. Allman lias published a monograph of the Gymno- 
blastic or Tubularian Hydroids (Ray Soeiety, London : 1871. 
Part I. The Hydroida in General. Royal 4to, pp. xxii, & 154, 
pis. 1-12). This important work, the result of many years’ 
patient and enthusiastic investigation, is preceded by a very full 
and clear glossary of the terms emjiloyed, which, however, are 
too numerous to be noticed and defined in detail. The author 
adopts the following divisions of the Coelenterata ; — 
f Actinozoa. 
Ctenophora. 
Discophora. 
Lucernarise. 
Hydroida. 
Siphonophora. 
He awaits the result of further investigations before placing 
the tubulate and rugose corals among the Hydrozoa, as proposed 
by Agassiz. A full history of the progress of the study of the 
Hydroida is then given ; and the remainder of the present part 
of the work contains a very full account, illustrated by numerous 
woodcuts, of their morphology and physiology. Under the term 
'' zooids ” he would include not only the free medusiform buds of 
the Hydroida, but also the fixed hydranths and gonophores, 
which never attain a developed medusiform structure, as well as 
the simple generative sacs developed on the radiating canals of 
Obelia, Thaumantias, &c. ; whereas he rigidly excludes all mere 
organs, however capable they may be of temporary self-mainte- 
C(ELENTERATA. 
Hydrozoa. 
