72 TUFTS COLLEGE STUDIES, VOL. IV, No. 7 



The only other known species, O. protonema Stahl ex Him, 

 1900, p. 374, PI. LIV, fig. 396, was found on moist earth near 

 Strasbourg in 1877, but does not appear to have been found 

 elsewhere. O. albcmarlensc is larger throughout, the upper 

 part of O. protonema being only about 7 /* diam., and is also 

 distinguished by the scrobiculate mesospore and the inferior 

 pore. Like O. protonema it is found in company with Botry- 

 Jium, Vaucheria, Riccia, etc. 



Page 279, for Key to the Species of Endoderma, substitute, 



I. Kndophytic, marine. 2. 



I. Epiphytic, fresh water. 5. 



2. ID leaves of /ostera. 3. E. pfrforans. 



2. In marine algae. 3. 



3. Cellt mostly irregular. 2. E. viride. 



3. Cells mostly cylindrical. 4. 



4. Cells 5- 10 M diam. I. E. Wittrockii. 



4. Cells 2-6 M diam. 6. E. Jilifortne. 



5. Cells sobglobose to ellipsoid. 4. E. Pithophorae. 



5. Cells much flattened. 5. E. polytnorphum. 



Page 280, after description of E. POLYMORPHUM, add, 

 6. E. HILIPORMK Collins & Hervey, 1917, p. 39. Filaments 

 branched laterally and dichotomously ; cells cylindrical, 6 ft 

 diam. below, tapering to 2 /A near apex : sporangia formed from 

 any cell of the older part, depressed hemispherical, 6-12 ft diam. ; 

 bristles continuous with the cell, 4 p. diam. at base, tapering to 

 2 /*. In wall of Lyngbya conferuoidts Ag., Bermuda, Collins. 



Page 281, change generic character of CHAETOSPHAERIDIUM 

 in first three lines as follows : 



Cells globose, ovoid or hemispherical, with one or more disk- 

 shaped chromatophores, each with one pyrenoid. 



For Key to the Species of Chaetosphaeridium, substitute, 



i. Utricles evanescent ; general gelatinous coating conspicuous. 



I. C. globosum. 

 I. Utricles well develeped ; gelatinous coating inconspicuous. 2. 



2. Cells globose, chromatophore single. 2. C. Pringsfieimii. 



2. CelU ovoid, chromatophores two. 3. C. ovalis. 



After description of C. PRINGSHEIMII, add, 



Forma CONPBRTA Klebahn, 1893, P- 3<>7. PI- XIV, fig. n. 

 Cells closely compacted, often seeming to form a layer ; utricles 

 very short. Wis., G. M. Smith. Europe. 



