56 COLLIXS AND HERVEY. 



been some question as to whether the distinction between these two 

 species should be based on the size of the utricles, or on the presence 

 or absence of compression; the matter ip fully discussed by Bornet, 

 1892, p. 216. We have adopted the former plan. It must be kept in 

 mind that in actively growing plants or parts of plants, small and 

 immature utricles occur among those of normal size. C. decorhcatum 

 sometimes grows to a large size; one plant which we found growing 

 below low water mark in Harrington Sound was nearly a meter long 

 and over 10 cm. wide in the expanded part; it was the largest alga we 

 have seen in Bermuda, except possibly some Sargassum. It is un- 

 fortunate that the rather appropriate name of elongatum should have 

 to be replaced by the quite inappropriate decorticatum, but as shown 

 by Howe, it seems inevitable. 



Var. clavatum var. nov. Fronde habitu formam cylindricam C. 

 decorticati approximante, sed substantiae firmioris, vix gelatinosa, 

 colore laete viridi; utriculis forma multo variantibus; aliis cylindricis 

 vel leviter clavatis, 80 X 480 /j,; aliis 500 /ji longis, sursum dilatatis 

 ad caput subsphaericum 145/^ diam.; aliorum inflatione terminaU 

 ad 200 ju diam., a parte subcylindrica minus distincta; aliis obcam- 

 panulatis, 650 /x longis, 350 n diam., apice spatio brevi paullo latiori- 

 bus; aliis turbinatis, 640 /^ longis, apice 470 /i diam.; inter omnes, 

 formis intermediis. 



Habit that of a rather densely branched cylindrical C. decorticatum, 

 but of quite firm substance, hardly gelatinous, color light green. 

 Utricles very variable in form; some cyclindrical or slightly clavate, 

 SOX 480 /u; some 500 /i long, increasing in size upward to 112 ;u, 

 then with a subspherical head 145 n diam. ; in others the capitate 

 swelling up to 200 n diam., but less sharply marked o£P from the 

 subcyclindrical part, 120 fj. diam. ; others inverted bell-shape, 650 n 

 long, 350 M diam., somewhat wider for a short space at the truncate 

 top; others turbinate, 640 ;u long, 470^ wide at top; with all inter- 

 mediate gradations. 



The largest utricle observed was 980 ii long, 480 n diam. The plant 

 is so firm in texture that it does not collapse when taken from the 

 water; but when dried it is thin and papery. Sporangia ovoid, largest 

 at the middle, obtuse at each end; sporangia apparently not mature, 

 160 X 64 fi, 275 X 105 m, 280 X 100 ju; mature sporangia, packed 

 with spherical spores about 12 fi diam., 190 X 100 /z, 240 X 120 ju. 

 Type specimen, from stone wall at Inlet, by Frascati Hotel, Dec. 20, 

 1912, Hervey, No. 7322 in Collins herb. Also at Devonshire Bay, 

 Gravelly Bay, Feb., Causeway, March, Hervey. 



