96 Howe: Notes ox Bahaman algae 



branches of the third (and even the fourth) order are in harmony 

 with the variations which the recent researches of Dr. Livingston * 

 might lead us to expect would occur in a transition from salt to 

 fresh or slightly brackish water. The variety laxus is almost des- 

 titute of the yellowish staining matter which manifests itself so 

 conspicuously in ordinary specimens of this genus whether dried 

 or preserved in fluids. In all conditions of Coccocladus, the spor- 

 angia appear to mature almost simultaneously in all parts of a 

 plant, so that a considerable number of fertile individuals is needed 

 to follow out the stages of spore-formation. In Dr. Coker'? ma- 

 terial of the variety laxus, there occur two or three plants with 

 smaller pyriform-obovoid sporangia showing numerous chloro- 

 phyl-bodies, but apparently no spores ; these we take to be imma- 

 ture aplanosporangia, but in the absence of direct observation of 

 intervening stages the possibility that they represent sporangia of 

 a different sort has suggested itself. 



Coccocladus occidentalis laxus evidently has a closer affinity 

 with Coccocladus occidentalis Conquerantii,! judging from 

 Cramer's description, than with the typical C. occidentalis, but, we 

 believe, differs too much from that to bear the same varietal 

 name. The sporangia of C. occidentalis Conquerantii, according 

 to Cramer, are at most only slightly ellipsoidal and occur only 

 on branches of the first two orders. The number of spores to a 

 sporangium and the size of the spores, characters which are in 

 part relied upon by Cramer to separate his Botryophora Con- 

 qucrantii from his B. occidentalis, appear in a considerable series 

 of specimens of this genus now accessible to be extremely variable 

 and unreliable for a specific separation. And Cramer's selection 

 of a comparatively few-spored form for the typical C. occidentalis 

 is hardly justified in view of Harvey's description of the spores as 

 "innumerable," a characterization that is well substantiated by 



* Livingston, I!. E. On the Nature of the Stimulus which causes the Change of 

 Form in Polymorphic Green Algae. Mot. Gaz 30: 289-317. pi. i~, 18. 1900. 



. The Role of Diffusion and < tsmotic Pressure in Plants. Dec. Publ. Univ. 



Chicago, II. 8. 1903. 



f Dasycladus Conquerantii Crouan ; Schramm & Maze, Alg. Guadeloupe, 47 

 1865. Maze & Schramm, Alg. Guadeloupe, 10S. 1 870-77. 



Botryophora Conquerantii (Crouan) Cramer, Neue Denkschr. Schweiz. Xaturf. 

 Ges. 32 : 6. //. 4. f. 1. 1890. 



