WELWITSCh's AFRICAN FRESHWATER ALG.E. 121 



40. C. multiordinatum, sp. n. (tab. 367, fig. 8). C. mediocre, 

 circiter li-l^-plo longius quam latius, profunde constrictum, sinu 

 angusto-lineari extremo subampliato ; semicellulae pyramido-trapezi- 

 formes, apicibus late truncatis, lateribus subrectis (leviter convexis), 

 angulis leviter rotundatis ; a vertice visse ellipticfe in medio utro- 

 bique leviter et late tumidfe ; a latere visae globoste ; membrana 

 uiiiformiter granulata, granulis iu seriebus verticalibus (circ. 8) et 

 obliqnis, scrobiculis parvis G circa granulum unumquemque in 

 forma bexagona ordinatis, cum lateribus oppositis duobus form^e 

 bexagonfe liorizontalibus. Long. 61'5-73 /x; lat. 51-62 /x ; lat. 

 apic. 25-33 /x; lat. istlim. 1-1-5-21 ji; crass. 35 /x. 



Puugo Andongo. In staguis prope Anbilla (Condo) ; March 

 1857. No. 177. 



This is nearest to C. decoratum West & G. S. West (in Trans. 

 [Attn. Soc. 2ud ser. v. 61, t. vii. f. 21), but it is easily distinguished 

 by its shorter cells, its smaller size, its round (not triangular) 

 Ecrobiculations surrounding the granules, as well as its wider apex. 



This is the only species we know which has the two opposite 

 sides of the hexagons of scrobiculations surrounding each granule, 

 horizontally disposed. 



41. C. BiARGARiTATUM (Luud.) Koy & Biss. in Jouin. Bot. xxiv. 

 194 (1886); Koy in Ann. Scott. Xat. Hist. 167, t. ii. f. 12 (1894j. 

 (.'. latiun 13reb. var. inan/aritatiiin Lund, in Xovct Acta B. Soc. Scient. 

 Ups. ser. 3, viii. 26 (1871). 



Forma minor Boldt. in Bill, till Sv. Vet-Akad. Handl. Bd. 13, 

 Afd. 3, no. 5, 26 (1888). Long. 44-60 /x ; lat. 38-47 /x; lat. isthm. 

 12-5-13-5 /x. 



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



42. C. PoRTiANUM Arch, in Q. J. 21. S. viii. 235-6, t. xi. f . 8, 9 (1860) ; 

 in Pritch. Inftis. 733 (1861); liabenh. Fl. Exirop. Ahj. iii. 160 (1868). 



Var. oRTHosTicHUM Schmidle in Bcricht. Dentsch. But. Ges. Bd. xi. 

 Heft. 10, 549, t. xxviii. f. 7 (1893). Forma minor, semicellulis 

 exacte ellipticis (ut in forma typica), granulis in seriebus verticalibus 

 distinctis 9 (circ.) ordinatis. Long. 25 /x ; lat. 19 /x; lat. isthm. 

 8-5 /x ; crass. 12-5 /x (tab. 308, fig. 9). 



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



This approaches C. ncphroideum Fioy & Biss. (in Ann. Scott. Nat. 

 Hist. 1894, 169, t. ii. f. 3), which seems to differ from C. Fortianum 

 var. nephroidenm Wittr. both in its smaller size and in the regular 

 arrangement of its granules. 



43. C. TRACHYCYRTUiM Reiusch, Contrib. Ahj. et Fang. 83, t. xviii. 

 f. 1 (1875). Forma lateribus minus retusis. Long. 15/^; lat. 14-5'jtA; 

 lat. isthm. 4-5 /x ; crass. 7*5 (x. 



Huilla, Inter PorpJujrosiiilumein Notarisii Kiitz. in udis sylvaticis 

 et apricis inter Monino et lac. Ivantala ; April 1860. No. 14. 



44. C. PUNcruLATUM Br6b. in Mem. Soc. Sciences Nat. Cherbourg, 

 iv. 129, 303, t.i.f. 16(1856); Klebs in Schrift. phys.-iikun. Gesellsch. 

 KiJnignberg, xx. 37, t. iii. f. 50, 51 (1879). Lat. = long. = 18 /x ; 

 lat. isthm. 6 p. ; crass. 9 /x. 



Huilla. Iu rivulis prope Lopollo ; May 1860. No. 187. 



