ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
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one cystocarp is produced. Fertilization is effected by the fusion of 
the polliuoids with the trichogyne ; but the complete process is an 
indirect one. The carpospores are not produced from the cells im- 
mediately beneath the trichogyne, but are developed in chains from the 
medullary network of cells continuous with that from which the tricho- 
phoric cells and the trichogyne arise. Each trichogyne is in communi- 
cation, by means of the trichophoric apparatus, which consists of from 
one to three cells, with the subcortical weft of hyphae ; and this is in its 
turn continuous with the longer and larger medullary cells. The deve- 
lopment of the carpospores commences only after fertilization ; but not 
unfrequently a number of subsidiary vegetative cells are formed round 
the trichophore, even before fertilization, and these are readily mistaken 
for carpospores. 
Cystocarps of Callophyllis and Rhodymenia.* * * § — Mr. J. B. Carruthers 
describes the cystocarps in several seaweeds which he refers to the 
genera Callophyllis and Rhodymenia. The details of the development of 
the fruit of Callophyllis obtusifolia do not agree with Agardh’s account 
of the structure of that genus, but rather with the mode of development 
which Bornet has described for the cystocarps of Gymnogongrus and 
Callymenia , and Schmitz for those of Gigartina and Chondrus. 
Fossil Corallinacese and Codiaceae.t — According to Herr A. Roth- 
pletz the fossil species of Lithothamnion cannot be safely determined by 
the size of the cells, which is variable. The mode of formation of the 
tetraspores furnishes a better character for their arrangement under three 
groups, viz. (1) tetraspores placed singly on zonal areas in the calcified 
tissue (L. cenomanicum sp. n., turonicum sp. n., gosaviense sp. n., num- 
muliticum , torulosum ; (2) tetraspores placed singly in small lumps in the 
calcified tissue ( L . ruganum sp. n.) ; (3) tetraspores collected into con- 
ceptacles outside the tissue ( L . racemus). Of these the first is much the 
oldest group. 
The author further describes a new genus and species Sphserocodium 
Bornemanni belonging to the Codiaceae. The thallus spreads over foreign 
bodies, especially the stalks of crinoids and fragments of mussel-shells. 
Like Codium it forms terminal sacs and lateral swellings (sporanges) ; 
but the sporanges are globular. Giovanella, hitherto referred to the 
Foraminifera, is a genus of Codiaceae, nearly allied to Sphserocodium. 
New Australian Freshwater Algae.! — Prof. M. Moebius describes 
a large collection of freshwater algae from Brisbane, including several 
new species. Among the more interesting additions are two new species 
of Coleochsete , C. Baileyi and conchata. In the former zoospores are 
produced in all the ceils of the erect branches. The oogones appear to 
detach themselves very readily from the thallus. The latter species has 
a very peculiar cortication of the oogones. 
Muciferous tissue of the Laminariaceae.§— M. L. Guignard has 
investigated the structure and development of the mucus-canals or 
* Journ. Linn. Soc. (Bot.) xxix. (1892) pp. 77-86 (1 pi.). 
t Zeitschr. Deutsch. Geol. Gesell., xliii. (1891) pp. 295-322 (3 pis.). See Bot. 
Centralbl., 1. (1892) p. 391. f Flora, lxxv. (1892) pp, 421-50 (22 figs.). 
§ Aun. Sci. Nat. (Bot.), xv. (1892) pp. 1 46 (20 figs.) ; and Comptes Reudus, 
cxiv. (1892) pp. 139-41. 
