158 MESSRS. W. WEST AND G. S. WEST ON 
S. CLOSTERIUM SUBCAPITATUM, n. sp. (Pl. 8. figs. 1-3.) 
Cl. mediocre; cellulis diametro circiter llplo longioribus, 
subrectis, ventre recto vel leviter concavo, dorso convexo et in 
medio retuso, polos versus attenuatis, polis valde dilatatis (sub- 
capitatis) ; membrana admodum punctata, luteola vel luteo- 
fuscescens, polis bene fuscis. 
Long. 253-265 u ; lat. max. 13-25 p ; lat. med. 21-23 u; lat. 
apie. 11 p. 
The strongly punctate membrane sometimes gives the margin 
a rough appearance. This species might be compared with 
C. balmacarense, W. B. Turn. in Naturalist (1893), p. 347; 
Roy and Bisset, in Ann. Scot. Nat. Hist. (1894) p. 243, t. 4. 
f. 6. 
9. C. LeavMEN, n. sp. (Pl. 8. figs. 5-7.) 
C. submediocre, subrectum: cellulis diametro 5-6plo longi- 
oribus, ventre recto, dorso leviter convexo, polos latos versus 
sensim attenuatis, polis rotundo-truncatis et levissime retusis ; 
membrana hyalina, achroa, glabra; pyrenoidibus in serie unici, 
in semicellulà unáquáque circiter 3. 
Long. 153-176 u ; lat. 26-30 u ; lat. apie. circ. 10 p. 
We found this species originally from Huilla, Angola, West- 
Central Africa, but as it was only a single semicell we wished to 
see more of it before describing it. 
It comes nearest to C. rectum, Gutw. (in Naklad. Akad. Uniej. 
Krakow (1896), p. 35, t. 1. f. 3). We consider that Gutwinski's 
species is probably a form of Penium Libellula (syn. P. closteri- 
oides); thisform with the projecting median sutures we mentioned 
as occurring at Capel Curig, N. Wales (vide West, in Journ. 
R. Mier. Soc. (1890) p. 286). 
10. C. Toxon, West, in Journ. Linn. Soc. ( Bot.) xxix. (1892), 
p- 121, t. 19. f. 14. 
Forma paullo brevior; membrana lutescens. 
Long. 163 u; lat. 9:5 p; lat. apic. 575 p. 
ll. C. PULCHELLUM, n. sp. (Pl. 8. figs. 8-9.) 
C. parvum ; cellulis diametro circiter 7plo longioribus, leviter 
et regulariter curvatis, polos versus gradatim attenuatis, pol 
subobtusis ; membrana glabra, fusca vel fusco-rubra ; pyrenoidr 
bus 2 in semicellula unáquáque. 
