SOME KOKTH AMERICAN DESMIDIE^. 245 



subtrilobae, lobis lateralibus subrectangularibus, lateribus leviter divergenti])us, 

 angulis superioriljus emarginatis, lobo polari latissimo truncato ad medium retuso, 

 angulis subacutis ; semicellulae tumore mediano, intra marginem angulorum sujx^ri- 

 orum et inferiorum loborum lateralium granulo singulo instructe, intra apicom 

 granulis 4 instructse ; a vertice visae oblongae polis rotiindatis, latere unoquoque 

 prope polos papilla singula instructae, tumore truncato mediano utrobique; a latere 

 vis9B ovato-ellipticae, apice subtruncato, tumore truncato infra medium utrobique. 

 Long. 27 /» ; lat. 23 joo ; lat. apic. 14'5 ^ ; lat. istlun. 45 ^ ; crass. 13-5 /u. 



59. EuASTRUM SUBORNATUM, nov. sp. (PI. XIV. fig, 30.) R minimum, paullo latius quam 



longius, profunde constrictum, sinu lineari ; semicellula3 subtrilobae, lobis lateralibus 

 rotundatis et granulatis, lobo apicali breviore late emarginato-truncato, apice 

 levissime 4-undulato, in centro cum annulo granulorum 5 circJi grauuluni centralem ; 

 a vertice visae anguste oblongas, in medio valde inflatae (et trigranulatjje) utrobique 

 polis angulari-capitatis et granulatis, lobo polari quadrato-oblongo ; a latere visa3 

 sub.trilobye, granulatie, apicibus truncatis. 

 Long. 16-5-17o u; lat. 19-5-22 /n; lat. apic. 8-10 n; lat. isthm. 6-9 /n; crass. 13-5 n. 



60. E. VALiDUM, nov. sp. (PL XIV. figs. 32, 33.) B. parvum, IJ-plo longius quam 



latius, profundissime constrictum, sinu angusto-lineari extremo leviter ampliato; 

 semicellulaj truncato-pyramidata), lateribus retusis, angulis inferioribus inflatis, 

 angulis superioribus subrotundatis et leviter incrassatis, apicibus latis truncato- 

 convexis retusis et leviter incrassatis in medio, intra angulos inferiores cum papillA, 

 parva, supra et juxta isthmum cum granido magno, in centro scrobiculo minuto ; 

 a vertice visae ellipticse cum papilla parva ad polos utrobique ; a latere visa? ovatae, 

 cum granulo juxta isthmum utrobique ; mcmbrana glabra. 

 Long. 28-30 /j. ; lat. 22 in ; lat. apic. 14'5 /n ; lat. istlim. 4"5 /u ; crass. 11 ju. 

 The nearest species to this is Cosmarlum subblnale, Lagerh. in Nuova Notixrisia 

 (2 Genu. 1893), p. 163 (C. Hmnmeri, Eeinsch, v. mbbinaley Nordst. Preshw. Alg. of New 

 Zeal. & Austr. p. 56, t. 6. fig. 7). 



Some considerable time after the above was written Cosmarium miedzyrzecense, 

 B. Eicbl. & Gutw. (Nonn. Alg. Nov. (1894) p. 4, t. 4. fig. 9), has been described and 

 figured. It comes very near the above species in front view, but it is much smaller, 

 relatively longer, has a diiferent apex, and is without the small granules present within 

 the basal angles of E. validum ; the vertical view is also quite different. 



61. E. TRIGIBBERUM, Wcst & G. S. West, in Trans. Linn. See. ser. II., Bot. v. (1895) 



p. 53, pi. 6. fig. 22. 

 Long. 26-5-29 ^. ; lat. 22-23 /u ; lat. lob. pol. 14-5-15'5 a« ; lat. isthm. 7 /* ; crass. 13-5 fx. 



(PL XIV. fig. 34.) 



The specimens observed were a little larger than those seen from Madagascar, but 



were otherwise almost identical with them. 



Genus Cosmarium, Corda; Halt's. 



62. C. Hammeri, Beinsch, Algenfl. Prankeu, p. Ill, t. 10. tig. 1. (C. homalodermum, 

 Nordst. in Ofvers. 8v. Vet.-Akad. Porh. (1875) n. 6, p. 18, t. 6. fig. 4.) 



SECOND SERIES. — BOTANYT, VOL. V. ^ ^^ 



