432 BULLETIN OF THE BUREAU OF FISHERIES. 



Genus i. Codium Stackhouse. 

 Codhim, Stackhouse, 1797. P- XVI. 



Frond of spongy texture, of very varying form, consisting of branching, continuous 

 filaments, their swollen ends "utricles" closely packed to form a cortical layer^no 

 asexual propagation known; sexual reproduction by motile biciliate gametes, produced 

 in subovoid gametangia, borne laterally on the utricles and separated from these by cross 

 walls; female gametes large, dark green; male gametes small, yellowish; the zygote, 

 formed by the union of a male and a female gamete, germinates immediately; female 

 gametes sometimes germinate parthenogenetically(P); male and female gametes usually 

 produced on different individuals, but sometimes on the same individual. 



About 30 species described, many on insufficient characters; in tropical and tem- 

 perate seas, mostly in warmer regions. This is the most northern station reported for 

 the genus in North America, and is probably its northern limit. 



The elongated forms of this genus are very variable. The characters on which 

 many species have been described the length of frond, amount of flattening, and 

 comparative length and breadth of utricles vary greatly and are often connected by 

 intermediate stages. 



At Beaufort the plants can be grouped around two types and are accordingly 

 described as two species, although it is by no means certain that these should be kept 

 distinct. 



KEY TO SPECIES. 



Frond more or less cylindrical except in the axils of the branches, abundantly branched 



i.C. tomentosum (p. 432). 



Frond more or less flattened, sparingly branched ? 2. C. decorticalum (p. 433.) 



i. Codium tomentosum (Hudson) Stackhouse. PI. LXXXV, fig. i. 



Fucus totnentosus, Hudson, 1732, p. 584. 

 Codium tomentosum, Stackhouse, 1797, p. XXIV. 

 Codium tomentosum, Harvey, 1858, p. 29 (in part). 

 Codium tomentosum, De Toni, 1889, p. 491. 

 Codium tomentosum, Collins, 1909, p. 388. 

 P. B.-A. Nos. 168, 1869. 



Frond erect, cylindrical, dichotomously branched, more or less fastigiate; surface smooth and soft; 

 utricles obovate-clavate, 100 to 150 mic., rarely 200 mic. in diameter(?), 3 to 6 diameters long, apex 

 obtuse, unarmed. 



North Carolina to Florida; West Indies; Europe; Asia; Africa; Oceanica. 



Beaufort, N. C.: Very abundant, attached to rocks, shells, etc., throughout harbor and on Fort 

 Macon jetties; less abundant on Shackleford jetties; very abundant on Bogue Beach after hard winds. 

 Wrightsville Beach, N. C.: Abundant in sound, July, 1909. Pawleys Island, near Georgetown, S. C.i 

 Fairly abundant in bay near inlet, August, 1909. 



This is the northern limit of this species reported for North America. It is common at Beaufort from 

 June to September, becoming less abundant during the autumn, and found only occasionally during the 

 winter and spring. The only trace of these plants observed in April, 1908, was a group of minute speci- 

 mens, 3 to 12 mm. long, on shells 15 cm. below low water, apparently just commencing their growth. In 

 May, 1907, no specimens were found in the harbor, but three pieces, 2 to 3 cm. long, were dredged on the 

 coral reef offshore, and a few small fragments were collected on Bogue Beach. Small specimens were 

 collected in Beaufort Harbor and on Fort Macon jetties in January and February, 1909, but none was 

 found at any other time during the winter. This may grow to a considerable size. The plant figured on 

 Plate LXXXV, figure i, found on Bogue Beach in October, had a radius of 30 cm. and, after the surface 

 water was removed with a towel, weighed 1.942 kg. (4 pounds 4.5 ounces). 



