420 BULLETIN OF THE BUREAU OP FISHERIES. 



Florida; southern California; warmer waters generally. 



Two or three small clumps, on rocks of Shackleford jetty, Beaufort, N. C., April, 1908. Fronds 6 to 

 23 cm. long. 



This, being a southern species, might be expected to occur at Beaufort throughout the summer, but 

 has been found only once, in April. Even then it was by no means a conspicuous part of the spring 

 flora. It is distinguished from E. intestinalis, which it resembles, by having smaller cells arranged in 

 regular series, a somewhat more delicate membrane, and a thicker wall between the cells. 



3. Enteromorpha intestinalis (Linnaeus) Link. 



Uha intestinalis, Linnaeus, 1755, p. 433. 

 Enteromorpha intestinalis. Link, 1820, p. 5. 

 Enteromorpha intestinalis, Harvey, 1858, p. 57 (in part). 

 Ulva enteromorpha var. intestinalis, Farlow, 1883, p. 43. 

 Enteromorpha intestinalis, Wolle, 1887, p. 107, pi. 135, f. 9-10. 

 Enteromorpha intestinalis, De Toni, 1889, p. 133. 

 Enteromorpha intestinalis, Collins, 1909, p. 904. 

 P. B.-A. No. 464. 



Frond simple or having at the base a few branches similar to the main frond, or occasionally a few 

 proliferations above; length varying from a few centimeters to several meters; diameter i to 5 cm.; at 

 first attached by a short, cylindrical stipe, but soon detached and floating; cylindrical or expanding 

 above, more or less inflated, often much crisped and contorted, and irregularly and strongly constricted; 

 cells 10 to 16 mic. in diameter, in no regular order; thickness of membrane varying from 50 mic. below 

 to 20 mic. above; cells in cross section 12 to 30 mic. * 



Along the shores of North America, except, possibly, the south Atlantic coast; salt water lakes of 

 western United States; Brazil; Europe; Japan. 



Fairly abundant on rocks of Fort Macon jetties, Beaufort, N. C., December, 1908. 



A very variable species, of which many forms have been described ; some of these in fresh water. 



4. Enteromorpha linza (Linnaeus) J. Agardh. 



Ulva linza, Linnaeus, 1753, vol. 2, p. 1163. 



Uha linza, Harvey, 1858, p. 59. 



Enteromorpha linza, J. Agardh, 1882, p. 134, pi. 4, f. 110-113. 



Uha enteromorpha var. lanceolata, Farlow, 1883, p. 43. 



Enteromorpha linza, De Toni, 1889, p. 124. 



Enteromorpha linza, Collins, 1909, p. 206. 



P. B.-A. Nos. 16, 967. 



Frond lanceolate or linear lanceolate, simple, i to 5 dm. long, i to 20 cm. broad; stipe short, 

 hollow; upper part of the frond flat, the membranes grown together as in Ulva, except at the edges, 

 where they remain free. 



Maine to West Indies; Alaska to California; South America; Europe; Tasmania. 



Abundant on rocks and shells in harbor and on jetties at Fort Macon and Shackleford, Beaufort, N. C. , 

 March to May, 1907-1909, at about low- water line; fairly abundant at about water level on buoy, Port 

 Royal, S. C., August, 1909. 



The forms of this species have been divided under forma crispata, with edges much crisped and 

 folded, and forma lanceolata, edges even or folded, not crisped. Only the latter of these occurs at Beau- 

 fort. The smaller specimens look like forms of E. intestinalis, but in the latter the frond, though often 

 collapsed, is tubular throughout; in E. linza the two membranes adhere except at the edges, where there 

 is a narrow, open space, around which the cells are arranged in cross section nearly in a circle. Different 

 plants vary greatly in their appearance, but the species is easily recognized by .the above characters. 



Genus 2. Ulva Linnaeus. 



Ulva, Linnaeus, 1753, vol. 2, p. 1163. 



Frond membranaceous, flat, consisting of two layers of cells, in any of which, except 

 those in the thickened base, zoospores or gametes may be formed, issuing through an 

 opening in the surface of the fronds, attached or free floating ; surface entire or perforate. 



Marine. 



