OQQ MESSES. AV. AVEST AND Gt. S. AVEST ON 



152. Staurastrum LEPTOCLADrM, Nordst. in Yidensk. Meddel. 1869 (1870), p. 228, t. 4. 

 fig. 57. 



Var. iNSiGNE, nov. var. (PL XVII. fig. 17.) Var. semicelluHs paulo brevioribus, 

 processibus extrorsum et valde curvatis, apicibus verrucis emarginatis quattuor 

 oniatis ; a vertice visis projectione mediana subemarginata utrobique instructis. 



Long. s. proc. 35 n, c. proc 76 |u ; lat. s. proc. circ. 17 /u, c. proc. 85 ;u ; lat. isthm. 8.5 /n ; 

 crass. 165 n. 



153. S. JoHNSONii, nov. sp. (PI. XVII. fig. 16.) [= S. leptocladum, N. L. Johnson, in 

 Bull. Torr. Bot. Club, xxi. (1894) p. 288, pi. 211. fig. 2.] S. mediocre, circiter duplo 

 latius quam longius (cum processibus), modice constrictum ; semicellulse subcam- 

 panulata3, ad basin truncato-inflatse cum annulis duobus granulorum (annulo 

 superiore plerumque irregulari), apicibus verrucis denticulato-truncatis 5-7 ornatis 

 et verrucis 5-7 intra marginem apicis, angulis superioribus in processus longos 

 subattenuatos leviter divergentes productis, margine superiore acute dentato, 

 raargine inferiore subundulato cum denticulis 4 prope basin, apicibus processuum 

 tridentatis; a vertice visas ellipticse, verrucis denticulato-truncatis utrobique et 

 serie verrucarum similium intra marginem unumquemque, polls in processus 

 longos denticulatos productis ; membrana delicatissima, sed sparsim punctata. 



Long. 38-5-44 /.; lat. c. proc. 82-5-88-5 n ; lat. isthm. 95-10 ^. 



This is a fairly constant species, and differs from S. leptocladum, Nordst., in the four 

 rows of denticulate verruca? at each apex, in the upper side of each process being much 

 rougher than the lower, except for the three to four minute teeth on the under side 

 near the base, as well as in the diff'erent base of the seniicells. The processes are 

 relatively shorter and stouter, and do not possess that graceful curve — first converging 

 and then diverging — so characteristic of ^S*. leptocladum, but are slightly divergent; 

 moreover, no specimen of the latter has ever more than two teeth at the apices ot the 

 processes, whereas *S'. Johnsonii has always three. 



1 4, S. Anchoea, nov. sp. (PL XVII. figs.21, 22.) S. magnum, duplo latius quam 

 longius (cum processibus), modice constrictum ; semicellulse campanulatye et leviter 

 inflate prope basin, apicibus truncatis et glabris, angulis in processus longos 

 imdulato-denticulatos leviter incurvatis productis, apicibus processuum tridentatis, 

 verrucis emarginatis 8 intra apicem unumquemque ; a vertice visae ellipticse, polls in 

 processus longos undulato- denticulatos productis, verrucis emarginatis 8 intra 

 marginem utrobique. 

 Long. 65-69 /i ; lat. c. proc. 119-136 fx ; lat. isthm. 12'5-15 n. 



155. S. ORNITHOPODUM, nov. sp. (PL XVII. figs. 18-20.) S. submagnum, profunde 

 constrictum, sinu extrorsum valde ampliato ; semicellulse subellipticai vel obsemi- 

 circulares, apicibus convexis spinis bi- vel trif urcatis prseditis, angulis in processus 

 breves crassos productis, annulo singulo (interdum annulis duobus) denticulorum 

 ornatis, apicibus processuum profunde trifurcatis, dentibus magnis divergentibus ; 



