254 Rhodora [OCTOBER 
18. Staurastrum muticum Bréb., var. minus Wolle. Diam. 21 p, 
length 24 m, isth. 6.5 u. Occasional. (H. C. no. 376.) 
19. Staurastrum punctulatum Bréb. Diam. 30 p, length 30 p, 
isth. 12 a. Usually joined in a series of two or more, often four. 
Common. (H. C. no. 394.) 
20. Staurastrum subarcuatum Wolle. Diam. 25 p without the 
spines. Common. Previously reported from Steep Brook, Massa- 
chusetts. (H. C. no. 347.) 
The collection made by Dr. Thaxter at Kittery, Maine, contained 
the following species : 
1. Hyalotheca dissiliens (Smith) Bréb, Diam. 22 p. Very com- 
mon, much of it in a fruiting condition. (H. C. no. 386.) 
2. Hyalotheca dissiliens (Smith) Bréb., var. Aitans Wolle. Diam. 
31 p, diam. of mucous sheath 7o u. Not so common as the typical 
species but not infrequent. It has been reported but once from New 
England, then from Amherst, Massachusetts. New to Maine. (H. C. 
no. 386.) 
3. AHyalotheca mucosa (Mert.) Ralfs. Diam. 19 p. Not infrequent 
New to Maine. (H.C. no. 371.) 
4. Bambusina Brebissonii Kg. Diam. including projections 22 y, 
average length of cells 25 p. Scarce. ( H. C. no. 342.) 
s. Desmidium aptogonium Bréb. ‘This species was noticed in look- 
ing over fresh material. 
6. Desmidium Baileyi Ralfs. Diam. 27 p, length 22 p, av. diam. 
of excavation 9 p, av. length of same 19 p. Frequent. (H.C. no. 344.) 
7. Desmidium cylindricum Grev. Diam. 36—46 m, sheath 63 p. 
Common. (H. C. no. 390.) 
8. Desmidium Swartzii Ag. Diam. 42pm. Large form. ( H.C. no. 
371.) Another measured diam. 36 4. (H.C. no. 390.) Common. 
9. Arthrodesmus ncus ( Ehrb.) Hass. This species was no- 
ticed in looking over fresh material. New /o Maine. 
10. enium Digitus (Ehrb.) Bréb. Diam. 48 p, length 164 p. 
Somewhat smaller than the measurements given by Wolle. Frequent. 
( H. C. no. 386.) 
11. Penium margaritaceum Bréb. Diam. 36 p, length 220 y. 
A more compact form than that given by Wolle as a comparison of the 
measurements will show. Not common. (H. C. no. 342.) 
12. Closterium acuminatum Kg. Diam. 25 p, length across ends 
190 4. Frequent. Reported from Bridgewater, Massachusetts. 
New to Maine. (H. C. no. 391.) 
