20G THE FRESHWATER ALG.E OF MAINE. 



PecUastrum angulosum Meneg. — P. Bonjanum Meneg. — P. Ehren- 

 heryii A. Braun. 



Ccclastnun microsponim Nag. 



Scenedesmus caudatus Corda. — 5. aciitus Meyen. — S. aciitus Meyeu 

 var. obliquus Eab. 



Ophiocytium. cochleare A. Braun. 



CJdorococcum (jiijns Rab. 



Dictyosphccriion Ehrenheryianum Niig. 



Palmodactylon simplex Niig. 



Schizochlamys gelatinom A. Braun. 



Palmella mucosa Kiitz. — P. hyalina Breb. 



Glaocystis vesiculosa Nag. — (x. rufescens A. Braun. 



Xephrocytinm Nayelii Gr. 



Chytridium globosum A. Braun. 



Olpidium ampullaceum A. Braun. This was on Cosmarium 

 De Baryi Arch. 



Desmidium. quadrangulatuyn Kiitz. 



Sphserozosma Aubertianum, nov. sp. Large, nearly as 

 long as broad, the incision narrowly acuminate, with two granules 

 on each side of the rounded semicells. Side view of semicells 

 almost globular, the granules having a linear arrangement. Lat. 

 18 — 23 /x; long. 16-5 — 19 // ; lat. isth. Q-o — 8 /x. This species 

 differs much from S. granulatum Roy et Biss., both in the number 

 and arrangement of the granules, in the much larger size, and 

 especially in the form of the isthmus. 



Penium Xavicula Breb. 



Clusterium costatum Corda. — C. pronum Breb. — C. Leihleinii Kiitz. 



Cosmarium. ovale Ralfs. — C. Ciicumis Corda. — C. moniliforme 

 Ralfs. — *C. truncatellum Perty. — "-(7. Piegnesii Reinsch. — C. Iceve Rab. 

 var. septentrionale Wille. — C. Meneghinii Breb. var. simplicimum 

 Wille. — C. galeritum Nord. — C. ochthodes Nord. — C. excavatum Nord. 

 var. duplo-inajor Lund. This was seen with zygospores several 

 times. — C. commissurale Breb. — C. suhcrenatum Hantzsch. The side 

 and end views of this were distinctly but faintly granulate. — C. 

 J^oeckii Wille. — C. sphalerostichum Nord. et Wittr. 



Tetmemorus Brebissonii Ralfs. — T. granulatus Ralfs. — T. lavis 

 Ralfs. 



Xanthidium fasciculatum Ralfs. var. hexagomun Wolle. — X. 

 Tylerianum W. West. 



^'Eiiastrum, sinuosum Lenor. — E. hinale Ralfs. var. elohatum Lund. 

 A form of the last species was seen with zygospore, which was 

 rotund, bearing simple spines rather sparingly. I believe a fully 

 developed zygospore has not been hitherto observed. 



Micrasterias pinnatijida Ralfs. — M. jnnnatijida Ralfs. var. trigona, 

 nov. var. End view trigonal with concave sides. 



Staurastrum tumidum. Breb. This exactly corresponded with 

 British specimens and with Ralfs' figure. — S. angulatum W. West, 

 var. suiiANGULATUM Hov. var. Evidently a variety of S. angulatum 

 with the apices of the angles more rounded and the sides more 

 convex. Long. 73 /x ; lat. isthm. 16 /x. — -'-S. apiculatum Breb. — **S'. 

 O'Mearii Arch. S'. hrrrispina Breb. — .S'. pseudo-pachyrhynchum 



