34 COLLINS AND HERVEY. 



Inlet, March, Hervey; Harrington Sound, April, Collins. In some 

 specimens cells may be found as large as 20 ft square, but in other 

 parts of the same individual they are of normal dimensions, little 

 over 12 /x. 



Forma submarina f. nov.; P. B.-A., No. 2161. Natans: frondi- 

 bus inflatis, contortis. 



Floating; fronds inflated, contorted. In extensive floating mats in 

 brackish water, near old race course, Dec., Collins. 



6. E. INTESTINALIS (L.) Grev. forma TENTHS Collins, 1903, p. 23; 

 1909, p. 205; P. B.-A., No. 2003. In brackish water, South Shore 

 marshes, Aug., Collins. The thickness of the frond, 20-30 n, is 

 greater than that of the plant on which this form was founded. The 

 latter grew in fresh water, remote from the sea; the present form, 

 growing in brackish water, may be considered as intermediate between 

 the form from fresh water and the typical species growing in the sea. 

 A specimen in the Kemp herb., marked Ulva linza, seems to be typical 

 E. intestinalis, but it is not in good enough condition for certainty. 



MONOSTROMA Thuret. 



1. Frond 25 p. thick or less, cells more or less in twos and fours. 



1. M. latissimum. 

 1. Frond 30 M thick or more; cells not in twos or fours. 2. M. orbiculatum. 



1. M. LATISSIMUM (Kiitz.) Wittrock, 1866, p. 33, PI. I, fig. 4; 

 Collins, 1909, p. 211; P. B.-A., No. 1859; Ulva latissima Kiitzing, 

 1856, p. 7, PI. XIV. On mangroves just below Flatts Bridge; on 

 Salicornia, Hungry Bay, April, Collins. This plant made its first 

 appearance at Flatts Bridge about the middle of April, 1912, and grew 

 rapidly. None was to be seen at the same station from July to Sep- 

 tember, 1913, nor elsewhere during those months. 



2. M. ORBICULATUM Thuret, 1854, p. 388; Wittrock, 1866, p. 37, 

 PI. II, fig. 6; Collins, 1909, p. 212; Alg. Am.-Bor. Exsicc., No. 173. 

 The material collected and distributed by Farlow is all that is recorded 

 for Bermuda. 



ULVA Linnaeus. 



1. Frond divided into linear lobes. 2. U. fasciata. 



1. Frond rounded or of irregular outline. 1. U. Lactuca. 



1. U. LACTUCA L. var. LATISSIMA (L.) De Candolle, 1805, p. 9; 

 Collins, 1909, p. 215. Rein; Moseley; April, June, Kemp, as U. 



