16 Transactions of the Society. 
Hob. Gun wen Moor, Cornwall. 
f. MAJOR. 
Long. cell. 77 ya ; lat. medio 29 ya ; lat. max. 32 • 5 
Hah. Lakes, Clifden to Roundstone, W. Ireland, 
var. pachyderma var. n. Fig. 36. 
Var. membrana cellularum 2 • 5-2 '8 ya crassa. 
Long. cell. 54 ya ; lat. medio 23 /a ; lat. max. 24*5 ya. 
Hab. Bowness, Lake District. 
Genus Kir chner iella Schmidle. 
K. obesa nob. [ — Selenastrum obesum West (Freshw. Alg. of 
Eng. Lake District in Journ. Roy. Micr. Soc., Dec. 1892, 
p. 734, pi. X. fig. 50-52)]. 
Hab. Bowness, Lake District. 
Since this species was described under Selenastrum, a new genus 
has been founded as Kirchneriella by W. Schmidle (Beitrage zur 
Algenfl. des Schwarz waldes und der Rheins, p. 16, tab. iii. figs. 1-3) 
to include a plant described as K. lunatum, which has the cells 
enveloped in a gelatinous matrix. In the specimens observed from 
Bowness the cells were in a practically invisible matrix which held 
them together at relative distances, and which also prevented other 
small objects from impinging on the families. This character, along 
with the irregularly grouped families, brings this species under 
Kirchneriella . 
Order Protococcace^ (includ. Palmellacejbi). 
Genus Scenedesmus Meyen. 
S. alternans Reinsch. (Algenfl. mittl. Frank., p. 81, tab. vi. fig. iii.). 
var. apiculatus var. n. Fig. 38. 
Yar. cum apiculo ad finem liberum utraeque celluke. 
Long. cell, (cum apic.) 7 * 5-9 • 5 ya ; lat. cell. 5-5 * 5 ya. 
Hah. New Forest, Hampshire. 
Class Phycochromace^:. 
Order Rivulariace^i. 
Genus JDichothrix Zanardini. 
D. INTERRUPTA Sp. n. 
Caespitibus penicillatis gregariis ; filis circiter 1-1 J millim. 
altis, multum ramosis subdichotome, 15-25 ya crassis in ramis 
superioribus ; ramis superioribus saepe adpressis ; vagina crassa, 
laevi, fuscescente in parte inferiore, uniformi, apice hyalino ; 
trichomatibus 2-3 (interdum 4) in vagina communi inclusis, 
aerugineo-olivaceis, tenuibus et interruptis, in pilum apice pro- 
duces; articulis diametro aequalibus vel lj-plo longioribus; 
heterocystis sphericis vel subhemisphericis, basilaribus. 
Crass, vag. basim versus 19-23 ya ; crass, trich. 2-2 *4 ya ; 
crass, heterocyst. 2 • 4-2 * 7 ya. 
Hab. Slieve Donard, Co. Down, Ireland. 
