Algce, Bacillarioo?, Pijeadoraphidepe, Nitzscliiaee?e, Iloiiioeocladia, 15 



cis, nouiminquam medio leniter constrictis, utroque (ine obtusis, 

 costis validis trausversis circ. 6 in 10 /.., inter quas stri.u bin^B mo- 

 niliformes lum subopposita^, tura alternantes adsunt. 

 In tripoli ad montes Labrouicos TuscicB (Castrac). 



SuBCL. PSEUDORAPHIDE^ 

 Fam. NITZSCHIACEiE 



Gen Nitzscliia Hassall., Brit. freshw. Alg., p. 435, (s. amplo). 



ValvfB carina instructa^, punctis carinalibus brevibus vel in costas 

 breves prolongatis, rarius totam valvara percurrentibus. Carina^ utrius- 

 que valvae diagonaliter oppositae. Frustula libera, raro tubis inclusa 

 vel in tabulas consociata. 



1. Nitzschia spectabilis (Ehr.) Ralfs., in Pritch. inf., pag. 78'^. Castr., ^g 

 1. c, p,245. Si/nedra spec(abf7,?s Ehr., Mikrog., Icon. pL- Permagna, 

 late linearis, utroque fine cuneato-truncata vel rotundata; mem- 

 brana connectivali latissima, subtiliter plicata; valvis linearibus sub 

 polis attenuatis plus minus arcuatis usque ad 450 a. raro ultra 

 longis, apicibus obtusis saepe rostrato-capitatis ; carina excentrica 

 punctis carinalibus 4-6 in 10 y.., in costam brevem prolongatis; 

 striis transversis distmctissimis 10 12 in 10 j. conspicue punctatis. 



In tripoli ad Montes Labronicos Tuscice (Castrac ). 



2. Nitzscliia cursoria (Donk.) Grun., in CI. et Gr., Arct. diat , 1880, 49 

 p. 89. Castr. 1. c , p. 245. BaciUaria cursoria Donk., in Trans. Mik. 

 Journ., 6, p. 16, t. III, f. 12. — Exacte linearis utroque fine truncata, 

 valvis lineari-lanceolatis, acutatis, 70 80^7, apicibus longe produ- 

 ctis ; carina centrali angusta, punctis carinalibus circ. 10 in 10 y.., 

 lineis accessoriis circumcarinalibus, medio 4 y.. inter se distantibus. 



In tripoli ad montes Labronicos Tuscice (Castrac). 



3. Nitzschia Entomon (Ehr.) Ralfs., in Pritch. inf, p. 780. Castrac , 50 

 Atti .Acc. Pont. N. Lincei, Marzo 1877, p. 245. ^ynef/m Entomon 

 Ehr., Mikrog. t. XXXIV, II, f. 5. — Elongatu, medio constricta, 

 apicibus cuneato-obtusis. 



In tripoli ad montes Labronicos TuscicB (Castrac). 



Gen. Homoeocladia Ag., Oonsp., p. 27. 



Frustula Nitzschiw, intra tubulos membranaceos simplices vel ra- 

 mosos subseriato inclusa. 



