338 X. zYGNEMACEa: (West). [Mougeotia 



5. Mougeotiae sp., I.e. 



HuiLLA. — Inter Utriculariam cymhantham, Morro de Lopollo ; April 

 1860. No. 179. 



Conjugation incomplete ; conjugating cells much bent. 



2. GONATONEMA Wittr. (1878). 



1. G. tropieum W. et G. S. West in Journ. Bot. 1897, p. 38. 



HuiLLA.— Alga laete viridia, lubrica ad rupes submersas de Morro de 

 Lopollo ; Feb. 1860. No. 186. Inter Temnogametum heterosporum, 

 Morro de Lopollo ; Feb. 1860. No. 172. In paludibus exsiccandia ; 

 April 1860. N<i. 176. Inter Microsporam LSfgrenii, Morro de Lopollo ; 

 May 1860. No. 182. 



This is a most characteristic apecies ; spores with processes of 

 this nature are possessed only by two other algse in the order 

 Ziignemacem, 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, I.e. 



HuiLLA. — In paludibus exsiccandia ; April 1860. No. 176. 



The fact that only a portion of the contents of the conjugating cella 

 participates in the formation of the zygospore indicates a relationship 

 to the fam. Hesocarpiece, although the arrangement of the chromato- 

 phores in the ordinary vegetative cells much resembles the arrangement 

 in the genus Zygnema (fam. Zygnemeie). The character of the 

 zygospores is, however, quite unique, and the plant has therefore 

 been placed in a new family, PyxisporecB . 



4. ZYGNEMA Ag. (1824). 



1. Z. erieetorum Hansg. in Archiv. Naturw. Landesdurchf. von 

 Bbhmen, Bd. vi. 155-6 (1888); W. et G. S. West in Journ. Bot. 

 1897, p. 39. 



Zygogonium erieetorum Kutz. Phyc. Gener. 280 (1843). 



PuNOO Andongo. — Inter Q^dngonii sp. ad limum juxta rivulum 

 de Casalal^ ipsius Praesidii ; Feb. 1857. No. 106. Inter (Edogonii 

 Rothii f. majorem ad ramuloa Podostemacearum in rivulis Preesidii 

 (CasalaW) ; March 1857. No. 105. Ad Podostemaceas (Tristicha 

 trifaria Tul.) in riv. de Cabondo ; Feb. 1857. No. 108. 



HuiLLA. — In udis sylvaticis et apricis inter Moniuo et lac. Ivantala ; 

 April 1860. No. U. In paludibus exsicoandis ; April 1860. No. 176. 



2. Z. spontaneum Nordst. Alg. et Char. Sandvic. 17, t. i. f. 

 23-24 (1878) ; W. et G. S. West in Journ. Bot, 1897, p. 40. 



HuiLLA. — Inter Gonatonema tropieum, Timnogametum heterosporv,m, 

 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. 



