18 CHLOROPHYCEAE 
1839). Lyngbya ferruginea Ag. is made a synonym of L. aestuarii 
by Gomont (Ann. Sci. Nat. Bot. VII. 16: 127. 1892) but he 
apparently does not cite any Peruvian specimen in showing the . 
distribution of this species. 
We have observed two or three undetermined species of 
Oscillatoriaceae in minute quantity attached to various Peruvian 
algae (e. g. Prionitis decipiens) in Dr. Coker's collections. 
Family SCYTONEMATACEAE 
PLECTONEMA Thuret, Ann. Sci. Nat. Bot. VI. 1: 375, 
379. 1875 
PLECTONEMA TEREBRANS Born. & Flah. Bull. Soc. Bot. France 
36: clxiii. pl. то. f. 5,6. 1889 
In old shells, with НуеЏа caespitosa Born. & Flah., etc., 
dredged near San Lorenzo, region of Callao, Feb. 5, 1907, Coker 
59 Р.Р. bi 
The filaments are 0.8—1.4 и in diameter, usually much con- 
torted, and rarely branching. 
CHLOROPHYCEAE 
Family ULVACEAE 
ULVA L. Sp: Pl. 1163. 1753 
(туа LACTUCA RIGIDA (Ag.) Le Jolis, Liste Alg. Mar. 
Cherbourg 38. 1863 
Ulva rigida Ag. Sp. Alg. 410. 1822. J. Ag. Till Alg. Syst. 3: 168. 
pl. 4.7. 110-122. 1882. 
Phycoseris rigida Kütz. Tab. Рћус. 6: pl. 23. f. II. 1856. 
In beach drift, La Punta, region of Callao, December, 1906, 
Coker 23 p.p.; on Glossophora Kunthii, in beach drift, same locality, 
Jan. 25, 1907, Coker 32 p.p. (young); growing in tide-pool, same 
locality and date, Coker 36; abundant on surf-washed rocks, 
Chincha Islands, June 18, 1907, Coker 193 p.p.; in same locality, 
July 13, 1907, Coker 402 p.p.; from drift on the beach, Pisco, July 
7, 1908, Coker 465 p.p.; Isla Vieja, Bahía de la Independencia, 
July 20, 1907, Coker 09640 p.p.; on rocks in the surf , Mollendo, 
August, 1908, Coker 565 p.p. 
The thallus in the mature Peruvian plants is mostly 80-120 в 
