176 welwxtsch's afeican feeshwater alg.e. 



membrana dense punctata. Long. 32-5-35 /x ; lat. 26-27 /^ ; lat. 

 apic. 12-5-13-5 // ; lat. isthm. 25 [x; crass. 17-18 /x. 



Huilla. Inter Utriculariam, Morro de Lopollo ; April 1860. 

 No. 179. 



63, C. CucuRBiTA Breb. in Desmaz. PI. Cn/ptog. Fr. fasc. xxiii. 

 1103 (1841), in ed. i. ser. i. (1825-51) ; Ealfs, Brit. Besm. 108-9, 

 t, xvii. f. 7 (1848). Long. 29-31 /x ; lat. 15-19 /x; lat. istbm. 

 14-18 IX. 



Huilla. In paludibus exsiccandis ; April 1860. No. 176. Inter 

 Utriculariam, Morro de Lopollo ; April 1860. No. 179. Morro de 

 Lopollo ; Febr. 1860. No. 192. 



All the African examples are more densely and minutely punc- 

 tate than the typical plant. 



Forma minor. Long. 21-24 /x; lat. 12-5 [x; lat. isthm. 11 //. 



Huilla. Cum forma typ. Nos. 176 and 179. 



Var. MINIMUM, var. n. Long. 12-5 jx ; lat. 7*5 /x ; lat. isthm. 7 /x. 



Huilla. Cum forma typ. No. 179. 



64. C. palangula Breb. iu Ealfs, Brit. Desm. 212 (1848). Forma 

 semicellulis punctis insignis et densis, subirregulariter dispositis. 

 Long. 36 jx; lat. 15 /x; lat. isthm. 13*5 /x. 



Huilla. In uliginosis editioribus prope Humpata, Empalanca 

 et Lopollo; May 1860. No. 15. 



13. Staurastrum Meyen (1829). 



1. S. LEPTODERMUM Luud. in Nova Acta R. Soc. Scient. Ups. 

 ser. 3, viii. no. ii. 58, t. iii. f. 26 (1871). 



Forma minor. Forma subminor, angulis minus productis. 

 Long. 46 fx ; lat. cum spin. 42 /x ; lat. isthm. 18 /x. 



Libougo. Ad margines flum. Lifune ; Sept. 1858. No. 204. 



2. S. tripodum, sp. n. (tab. 369, fig. 11). S. parvum, IJ-plo 

 latius quam longius (sine spinis), profunde constrictum, sinu aperto; 

 semicellulne transverse subrectangulares, latere ventrali inflato, 

 angulis basalibus dentato-mamillatis, marginibus lateralibus leviter 

 convergentibus apices versus, apicibus pnene rectis (leviter convexis), 

 spina longa valida suberecta (long. 13 /x) ad angulum superiorem 

 unumquemque ; a vertice visse triangulares, lateribus leviter cou- 

 cavis, angulis acutis (submucronatis), prope et intra apicem anguste 

 uniuscujusque spina valida multe abbreviata ut visa ; membrana 

 glabra. Long, sine spin. 21 /x, cum spin. 46 /x ; lat. 26 /x ; lat. 

 isthm. 9 /x. 



Huilla. In paludibus exsiccandis ; April 1860. No. 176. 

 This species and S. xiphidiophorum Wolle are respectively simple 

 and complex species of a distinct section of this genus. 



3. S. crux-alternans, sp. n. (tab. 369, fig. 14). S. miuutum, 

 tarn longum quam latum (cum processibus), sinu semicirculari (cum 

 latere inferiori processuum), parte mediana cellularum subcylindrica, 

 partibus apicalibus cellularum transverse subelliptic^e, polis iu pro- 

 cessus breves latos glabros truncato-emarginatos productis, apicibus 

 leviter convexis granulo singulo utrobique prope sed supra basin 

 processus uniuscujusque ; a vertice visfB quadrangulares lateribus 



