OF THE THIRD TANGANYIKA EXPEDITION. 179 
Crass. trich. 0:7-0:8 рш; long. tot. trich. 21-275 д. 
Tanganyika.—In plankton, near Chamkaluki (15 Nov. 1904; no. 160) and 
near Kala (19 Nov. 1904 ; no. 170). 
This species occurred in abundance in the two above-mentioned collections. 
The trichomes are exceedingly narrow and are chiefly remarkable for the 
laxness of the spirals. Some of them were very short, scarcely exceeding 
a single turn of the spiral, whereas others possessed as many as fourteen 
turns and reached a length of 275 y. 
333. SPIRULINA Princeps, W. у G. 5. West, in Trans. Linn. Soc. ser. 2, 
Bot. vi. (1902) p. 205.—8. Gomontii, Gutw. in Bull. Acad. Sei. Cracov. 
(1902) p. 613, t. 40. fig. 69. S. gigantea, Schmidle, in Engl. Bot. Jahrb. 
xxxii. (1903) p. 59, t. 1. Во. 5. 
Crass. trich. 3°5-4°8 ш. (РІ. 9. fig. 5.) 
Nyasa.—In swamp, Karonga (2 July, 1904 ; no. 34). 
This species has а wide distribution in the tropics, having been described 
from Java, Ceylon, and Central Africa. Unfortunately, it was described as 
а * sp. nova" in each case, the name Spirulina princeps being the first one 
given to it. 
The cell-contents are of a bright blue-green colour, and homogeneous in 
charaeter except for a few scattered refractive granules, which are rarely 
absent. The trichomes are slightly variable in thickness, and in the width of 
the spiral and relative distance apart of the turns, but to my mind these 
differences are not of a specific nature. The width of the spiral varies within 
the extremes even in a single trichome, and the distance between the turns 
of the spiral varies at different parts of the same trichome. 
The following table shows the differences of measurement between the described forms :— 
| i m mE | | B YA 
" Thickness | Diameter Distance apart | 
Locality. of trichome, | of spiral. of turns. | 
E NEM _— — i —— 
Таха | 
(Sp. Gomontii ot 3.8 в | 88, ll p 
Gutwinski). | 
р BENE 
Ceylon. | — 455p 11-12 p 95 н 
| 
Africa (Nyasa) 
(Sp. gigantea of 3-4 p 11-16 в 
Schmidle). | 
Africa (Nyasa) | 
(coll. bv 3:5-4:8 п 9-12 p | 10-12, 
Dr. Cunnington). 
