254 



Of this species I have only found a few specimens. They 

 were dredged in rather deep water and were upon the whole 

 rather poorly developed. When in good condition this plant is 

 very characteristic, and easily known. Its chief peculiarities con- 

 sist in the very irregular subdichotomous branching, poorer in the 

 basal part, richer in the upper one, the branches on this account 

 being very closely placed at the top, and the whole thallus re- 

 ceiving a roundish outline. The thallus is terete or nearly so, and 

 of about the same size throughout the whole plant. 



A transverse section of the thallus shows that the central 

 axis is not very visible, the tissue consisting of roundish thin- 

 walled cells. The epidermal cell-layer is composed of very small 

 and nearly subquadratic cells. 



My specimens were sterile. Only dredged once in a depth of 

 about 15 fathoms. 



St. Jan: Off Eremitage. 



Geogr. Distrib.: West Indies, Florida. 



Subfam. 2. Chondrieae. 



Chondria Ag., Harv. 

 Subgenus I. Euchondria Falkenberg. 



1. Chondria polyrhiza Collins and Hervey. 



COLLINS, F. S. and A. B. HERVEY, The Alga? of Bermuda, p. 121, pi. 

 II, fig. 12. Phycotheca Bor.-Am., No. 2040. 



Of this species I have found a single specimen only, and 

 unfortunately it was dried. But it seems to agree quite well with 

 the description of COLLINS and HERVEY. 



The plant apparently forms a rather loose tuft, 5 to 6 cm 

 high. The ramification is very irregular, the branches spreading 

 out on all sides, varying greatly in length. There seems to be no 

 main stem. The distance between the branches and ramuli is 

 very variable. 



The branches and ramuli are narrowed at their base, taper- 

 ing upwards evenly into an acute apex. Here some small tricho- 

 blasts are found surrounding the conical, protruding growth-point. 

 The peculiar bunched rhizoids are numerous and break out 

 everywhere upon the thallus (Fig. 247). As pointed out by COLLINS, 



