174 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 12 



americana (1900b, p. 13), but without differentiating description. His 

 figures (1895b, loc. cit.) are similar to the most slender form of our 

 material. Lemoine (1929, p. 43 as Mesophyllum australe) recognized 

 two variants of L. australe from I. Coiba, Panama, namely v. minutula 

 and V. tualensis, which Foslie had described as formae from the western 

 Pacific (Foslie 1904, p. 24, pi. 2). The species as originally described 

 (Foslie 1895a, loc. cit.) showed segments which were relatively long and 

 slender, resembling Dawson's (1944, pi. 56, figs. 5-7, 9) material in part, 

 but the writer had none so slender, and none like f. hrachiata Foslie 

 (1904, pi. 2, figs. 25-38), which Dawson felt corresponded to some ma- 

 terial from the Gulf of California which he had collected. Rather, that 

 recorded here varies, portions approaching f. americana and others 

 approaching f. tualensis Foslie (1904, p. 24, pi. 2, figs. 10-17). Dawson 

 also had this plant {loc. cit. pi. 57, figs. 14-16). The writer did not find 

 anything corresponding to f. minutula Foslie (1904, p. 24). Curiously, 

 the f. americana is omitted from the posthumous work edited by Printz 

 (Foslie 1929, p. 39, pi. 17), although the later-described forms are in- 

 cluded. 



Mexico: Is. Revilla Gigedo, dredged in abundance from 37 meters 

 at sta. 132, Braithwaite Bay, I. Soccoro, no. 34-37 A (mostly f. tualensis), 

 2 Jan. 1934. Ibid., dredged sparingly from 63 meters at sta. 134, Sul- 

 phur Bay, I. Clarion, no. 34-73, (mostly f. americana), 5 Jan. 1934. 

 Ibid., rare as dredged at sta. 917 from 50 meters' depth, no. 39-25 (near 

 f. tualensis), 16 Mar. 1939. Ibid., rare as dredged from 36-38 meters 

 at sta. 919, no. 39-37 (near f. tualensis), 17 Mar. 1939. Nayarit, rare 

 as dredged from 22 meters' depth at sta. 970, off I. Maria Magdalena, 

 Las Tres Marias, no. 39-643B, (near f. tualensis), 9 May. 1939. Pana- 

 ma: dredged at Bahia Honda, no. 34-511 A (a little f. americana, mostly 

 f. tualensis), 22 Feb. 1934. Ibid., dredged from 27 meters' depth at 

 sta. 251 off Is. Secas, no. 34-521 B, 22 Feb. 1934. 



Lithothamnium Gottoni Lemoine 



Lemoine 1929, p. 57, pi. 2, fig. 8. 



Reported from I. Isabela, Archipielago de Colon. 



Lithothamnium pocillum Lemoine 



Lemoine 1929, p. 58, pi. 2, fig. 8. 



Reported without definite locality from the Archipielago de Colon. 



