Mr. J. Ralfs on the Nostochinez. 329 
3. T. Thwaitesii (Harv.). Filaments moniliform, slightly flexuose ; 
ordinary cells globular or nearly so ; vesicular cells larger, globular 
when interstitial, ovate when terminal, ciliated ; sporangia oval, 
eatenate. Spherozyga Thwaitesii, Harvey, Phycologia Britannica, 
t. 113 B (1847). 
Salt-marshes, Dolgelley, North Wales, and Hayle, near Penzance, 
J. R. ; Shirehampton, near Bristol, Mr. Thwaites ; Portbury, Somer- 
setshire, Mr. Broome ; near Hastings, Mr. Jenner. 
Trichormus Thwaitesti forms thin, gelatmous, dark green 
patches either on the damp soil covered at spring-tides or at the 
bottom of brackish ditches or pools. Filaments moniliform, 
elongated, pale bluish green. Ordinary joints nearly orbicular, 
except when dividing. Vesicular cells interstitial and terminal, 
ciliated, twice as large as the ordinary ones, ovate when terminal, 
otherwise spherical. Sporangia oval or nearly globular, larger 
than the ordinary cells, beginning near the centre of the fila- 
ment and forming chain-like groups of six or more together. 
Mr. Thwaites’s specimens vary in some respects from those | 
have gathered. I find the stratum very thin and tender, and the 
sporangia rarely produced ; but Mr. Thwaites informs me, that at 
Bristol, on the contrary, it forms, after a time, large, floating, 
gelatinous masses, and then abounds with sporangia. 
Trichormus Thwaitesti is more likely to be confounded with 
immature specimens of Spherozyga Carmichael than with either 
of the preceding species of this genus, especially as they often 
grow intermixed. In the present plant however the filament is 
longer, the ordinary cells are more globular, and the terminal 
cell either resembles the others or is ovate and vesicular. Its 
ciliated and globular vesicular cells distinguish it from 7. oscz/- 
lariotdes and T. recta. 
A specimen of Anabaina variabilis sent me by Professor Kiitzing 
is apparently identical with the present species ; but, as the former 
is described as lacustrine, with attenuated ends, I have thought 
it advisable not to unite them*. 
Puate VIII. fig. 4. a, immature filament ; 5, mature filament. 
4. T. oscillarioides (Bory). Filaments elongated, flexuose ; ordi- 
nary joints subquadrate, distinct ; vesicular cells barrel-shaped or 
elliptic, naked ; sporangia oval, catenate. Anabena oscillarioides, 
Bory, Dict. Class. d Hist. Nat. Spherozyga oscillarioides, Kiitz. 
Species Algarum, p. 291 (1849); Tabulee Phycologicee, t. 96. fig. 5. 
Trichormus affinis, Ralfs in lit. 
Brackish ditches. Shirehampton, near Bristol, Mr. Thwaites. 
* « Anabaina variabilis, lacustris, mollis, viridi-zeruginea ; trichomatibus 
attenuatis, erugineo-viridibus, laxe implicatis ; articulis ellipticis, majoribus, 
eranulosis.””—Kiitzing, Phye. Gener. p. 210. 
