THE PRESHWATEli ALGiE OF .MAJ)AGASCAK. 57 



66. CosMARiUM STJBPKOTUBEEANS, nov. sp. (PI. YI. fig. 40.) C. parviim, pauUolongius 

 quam latum, profunde constrictum, sinu linear! in extremo ampliato ; semicellulje 

 irregulariter subpentagonales, laterihus brevibus divergentibus, angulis lateral ibns 

 levissime rotundatis, apicibus conico-convexis ; a vertico vistc elliptica.^ in medio 

 utrobique magis inflatse ; a latere visse depresso-elliptica3 ; membrana irregulariter 

 punctata ; pyrenoidibus singulis. 

 Long. 19-21 yu ; lat. 18 jn; lat. isthm. 48 fx ; crass. 13-5 /n. 

 No. 1. 



This species comes near to C. protuherans, Lund. (Desm. Suec. p. 37, tab. iii. fig. 17)^ 

 but differs in front view in the conico-convex apex and more acute angles, in vertical 

 view in its broader inflation, and also in the very diff'erent form of the lateral view. 

 Prom C. pseudoprotuherans, Kirchn., it differs in its apex and lateral angles, its more 

 inflated vertical view, as well as in its much wider lateral view. 



67. CosMARirM QUADHOGRANULATUM, nov. sp. (PI. YI. fig. 38.) C. parvum, l|-plo longius 

 quam latum, profundissime constrictum, sinu angusto-lineari in extremo ampliato ;. 

 semicelkdse liexagono-hemisplia3rica% angulis lateralibus utrobique granule singulo 

 instructis, apicibus subrectis ; a vertice visa? ellipticag, granule ad polum unumquem- 

 que sito ; a latere visse subsphsericse ; membrana glabra ; pyrenoidibus singulis. 

 Long. 165 n ; lat. 13*5 n ; lat. isthm. 22 n ; crass. 8 /u. 

 No. 1. • 



The nearest species to this is C. pseudoprotuherans^ Kirchn., from which it differs in 

 its more rounded semicells, its narrower and deeper constriction, and in the presence of 

 a granule on each of the four lateral angles. C. piseudoprotuhercms, Kirchn., forma 

 " angulis superioribus semicellularum rotundatis," Borge (Chlorophylloph. fran Norska 

 Pinmarken, p. 12, tafl. i. fig. 10), is similar in form, but has the sides more divergent,, 

 is not so deeply constricted,. and has no granules. 



68. CosMARiLM MAMiLLiFERUM, Nordst. Dcsm. Brasil. t. iii. fig. 22. 



Var. MADAGASCARiENSE, nov. var. (PI. VL fig. 35.) Var. major, paene tarn latum quam 

 longum, semiceUulis depressis angulis rotundatis et leviter incrassatis, mamillis 

 majoribus, isthmo angustiore ; membrana minute punctata. 

 Long. 30-5 n ; lat. 26-5 |M,; lat. isthm. 5*5 //<; crass, sine nod. 16 /a. 



No. 3. .., ^__ ; . . 



69. CosMARirM SULCATUM, Nordst. De Algis et Characeis Sandwicensibus, p. 13, tab. i. 



figs. 18-20. 

 Long. 35-38-510,; lat. 31-34-5 />o; lat. isthm. 9-5-10-5^; crass. 18//-. (PL V. figs. 28^ 



29.) . • - 



No. 0. - ' 



SECOND SERIES. — BOTANY, VOL. V. ^ 



