338 x. zygnemace^e (West). [Mougeotia 
5. Mougeotiae sp., I.e. 
Huilla. — Inter Utriculariam cymbantham, Morro de Lopollo ; April 
1860. No 179. 
Conjugation incomplete ; conjugating cells much bent. 
2. G0NAT0NEMA Wittr. (1878). 
1. G. tropicum W. et G. S. West in Journ. Bot. 1897, p. 38. 
HtJILLA. — Alga laete viridis, lubrica ad rupes submersas de Morro de 
Lopollo ; Feb. 1860. No. 186. Inter Temnogametum heterosporum, 
Morro de Lopollo ; Feb. 1860. No. 172. In paludibus exsiccandis ; 
April 1860. No. 176. Inter Microsporam L&fgrenii, Morro de Lopollo ; 
May I860. No. 182. 
This is a most characteristic species ; spores with processes of 
this nature are possessed only by two other algae in the order 
Zygwmaceoe, viz. Mougeotia uberosperma and M. irregularis. The 
consecutive spores, which are very large, are alternately oblique, the 
cells containing them being very slightly bent alternately to the 
right and left. 
3. PYXISPORA W. et G. S. West in Journ. Bot. 1897, p. 39. 
1. P. mirabilis W. et G. S. West, l.c 
Huilla. — In paludibus exsiccandis ; April 1860. No. 176. 
The fact that only a portion of the contents of the conjugating cells 
participates in the formation of the zygospore indicates a relationship 
to the fam. Mesocarpece, although the arrangement of the chromato- 
phores in the ordinary vegetative cells much resembles the arrangement 
in the genus Zygnema (fam. Zygmmem). The character of the 
zygospores is, however, quite unique, and the plant has therefore 
been placed in a new family, Pyxisporecv. 
4. ZYGNEMA Ag. (1824). 
1. Z. ericetorum Hansg. in Archiv. Nfaturw. Landesdurchf . von 
Bohmen, Bd. vi. 155-6 (1888); W. et G. S. West in Journ. Bot. 
1897, p. 39. 
Zygogonium ericetorum Kiitz. Phyc. Gener. 280 (1843). 
Pungo Andongo.— Inter (Edogonii sp. ad limum juxta rivulum 
de Casalale ipsius Prassidii ; Feb. 1857. No. 106. Inter (Edogonii 
Rothii f. majorem ad ramulos Podostemacearum in rivulis Praesidii 
(Casalale) ; March 1857. No. 105- Ad Podostemaceas (Tristicha 
trifaria Tul.) in riv. de Cabondo ; Feb. 1857. No. 108- 
Huilla. — In udis sylvaticis et apricis inter Monino et lac. Ivantala ; 
April 1860. No. 14. In paludibus exsiccandis ; April 1860. No. 176. 
2. Z. spontaneum Nordst. Alg. et Char. Sand vie. 17, t. i. f. 
23-24 (1878) ; W. et G. S. West in Journ. Bot. 1897, p. 40. 
Huilla. — -Inter Gonatonema tropicum, Temnogametum Jieterosporum, 
etc., Morro de Lopollo ; Feb. 1860. No. 172. 
This most interesting species has very remarkable spores both with 
regard to their colour and markings. The original specimens from the 
Sandwich Islands described by Dr. Nordstedt had only aplanospores 
(hence the specific name) ; the African specimens have only zygospores. 
The relationship between the aplanospores and zygospores in this 
species is in all respects comparable to that between those of Z. 
pachydermum West : in the latter species the aplanospores are also 
smaller, globose, and possess a thinner membrane. 
