1910-1911.] The A /ga- Flora of Mid-Lothian. 359 



18. U. cequalis Kiitz. 



A far less common species, found only once at Harelaw Eeservoir 

 in May. 



19. U. subtilis Kiitz. 



This species of Ulothrix and its several varieties are frequently 

 met with, not only in stagnant and running water, but also in 

 most situations exposed to moisture. It is common on house 

 walls, below leaking rhones, and between flagstones in court- 

 yards. Everywhere in and around Edinburgh. The common- 

 est variety met with is var. variabilis Kirchn. 



20. Stichococcus hacillaris Nag. 



Very abundant on walls and stones, particularly on flower-pots, 

 and often associated with Ulothrix subtilis. 



21. S.Jlaccidus (Kiitz) Gay. 



On wet walls under dripping rhones, often with Ulothrix subtilis. 



22. Uronema confervicolum Lagerh. 



This rare Alga I have found only once, in a bog-pool at Bavelaw 

 Moor. August. 



Family — Chsetophoraceae. 



23. Chaeto'phora fisiformis (Roth) Ag. 



Elf Loch ; Royal Botanic Garden Pond ; ditch near Currie ; 

 Balerno. June, July. 



24. Ch. incrassata (Hudson) Hazen. ( = Ghoetophora endivcefolia Ag. and 



Ch. Cornu Bamce (Roth) Ag.) 

 Pond near Balerno ; Harelaw Reservoir. August. 



25. Ch. elegans (Roth) Ag. 



Elf Loch ; Craiglockhart Pond. July, August. 



26. Myxonema tenue (Ag.) Rabenh. (= Stigeocloniuni tenue Kiitz.) 



On dead leaves in rain-pools near Musselburgh, and also in similar 

 situations near Colinton and Balerno. April-July. 



27. Draparnaldia plumosa (Vauch.) Ag. 



Elf Loch (found only in 1909) ; ditch near Harelaw Reservoir ; 

 Bavelaw Moor. August. 



28. D. glomerata (Vauch.) Ag. 



Not uncommon in water-troughs or in running water ; Craiglock- 

 hart Pond ; Pentland Hills. May-August. 



Family — Microthamniaceae. 



29. Microthamnion Kiitzingianum Nag. 



In rain - pool on dead leaves near Swanston ; near Colinton ; 

 Balerno. June, July. 



30. M. strictissimum Rabenh. {— M. vexator Cooke). 



Bavelaw Moor. August. 



31. Gongrosira viridis Kiitz. 



On stones in running water, Colinton. August. 

 VOL. VI. 2 B 



