SOME NOETH AMElllCAN DESMIDIE^. 237 



28. Closterium Cynthia, De Not. Desm. Ital. p. 65, t. 7. %. 71 ; Cooke, Brit. Desm. 

 pp. 26-'27. 



Long. 73-76^ ; lat. 11-14 ;u. (PI. XIII. figs. 18, 19.) 

 Hab. Bog between Orono and Bangor, Maine. 



29. C. DiLATATUM, nov. sp. (PI. XIII. figs. 20-22.) C. mediocre, ccllulis diametro 

 8-plo longioribus, modiee curvatis, gradatim attenuatis ad polos, jjolis levitcr dilatatis, 

 apicibus angulari-convexis, angulis lateralibus polorum subincrassatis ; membrana 

 achroa delicatissim^ sed sparsini striolata, striis visis 6. 



Long. 218-228^; lat. 28-29 ^t; lat. apic. 9*5 /.. 



This species is less curved than C. lagoense, Nordst. (in Vidensk. Meddel. 18G9 (1870) 

 p. 203, t. 2. fig. 2), has fewer striae, and is less attenuated towards the poles, the dilated 

 portion of which is also shorter. 



30. C. cosTATUM, Corda, Almanach de Carlsbad, 1835, p. 124, t. 5. figs. 61-63 ; Jialfs, 

 Brit. Desm. p. 170, t. 29. fig. 1. Porma cellulis minus curvatis et apicibus 

 truncatis; striis 4 in 15*5-17;" ; membrana inter strias punctata. 



Long. 230-301 /u ; lat. 26-29 /i; lat. apic. 6-9 u. (PI. XIII. figs. 23, 24.) 



Genus Peniijm, Breb. 



31. P. ANKULAEE, West, in Journ. Bot. xxix. (1891) p. 354, t. 315. figs. 5, 6. 

 Long. ]90jii; lat. 23 /u ; lat. apic. 19 /n. 



Rab. Harvey Lake, Lycoming Co., Pa. 



Mr. N. L. Johnson of Ann Arbor informs us that he has this species in abundancf? 

 from Louisiana at a point over a thousand miles from the locality (Scarbro') in Maine 

 where it was first gathered. 



32. P. INCONSPICULM, West, in Journ. Boy. Micr. Soc. (1894) p. 4, pi. 1. figs. 6, 7. 

 Long. 19 /t ; lat. 58 ^u. (PI. XII. fig. 34.) 



Hab, Barvey I^ake, Lycoming Co., Pa. 



33. P. MiNUTUM, Cleve. {DocicUum minutum, Balfs.) 



Var. GRACILE, Wille, in Christ. Porh. Vidensk.-Selsk. 1880 (1881), n. 11, p. 51, t. 2. 

 fig. 33 ; West, in Journ. Linn. Soc. (Bot.) xxix. (1892) p. 129. (PI. XII. figs. 32, 33.) 

 Long. 142-268 i-i ; lat. 7-5-8-5 f,. 



Some of the forms noticed were much longer than Wille's, some being 30 times as 

 long as broad. 



Genus Cylindrocystis, Menegh. ; De Bary. 



34. C. ANGULATA, nov. sp. (PL XIII. figs. 25, 26.) (C. tumida, Wolle, Alg. U.S. 

 p. 23, pi. 56. figs. 7, S, non F. Gay.) C. submagna, circiter 2i-plo longior quam 

 latior, emarginatim constricta ad medium ; semicellula) truncal o-conicse, lateribus 

 rectis, apicibus subrectis angulis levissime rotundatis ; membrana scrobiculato- 

 punctata ; pyrenoidibus siAgulis magnis. 



Long. 65-69-5 m; lat. 29-31 /x; lat. apic. IPS^*; lat. constrict. 27-5-28-5^. 



SECOND SERIES. — BOTANY, VOL. V. ^^ 



