172 MINNESOTA BOTANICAL STUDIES. 



longitndini ramnlorum corticalium in diametro superante, filis mi- 

 noribus cylindraceis multis inter cellulos majores intersertis ; ramu- 

 lis corticalibus inferne parce dichotomis cellulis cylindraceis longi- 

 tiidine qiiadruphim latitudinis aequantibus compositis, superne di- 

 chotome corymbosis cellulis ovatis seu rotundis moniliformibus com- 

 positis ; in partibus vetustioribus frondis his ramulis dichotomis filis 

 moniliformibus simplicibus substitutis quae ex filis medullaribus 

 minoribus exorientur. 



North of Hotel, Waianae, Oahu. May 26, 1900. (J. E. T. 

 861 A) ; Laie Point, Koolauloa, Oahu. June 18, 1900. (J. E. T. 

 1007) ; Kealea Beach, Kauai. July 25, 1900. (J. E. T. 1202.) 



The frond is dichotomously decompound, but the numerous 

 lateral proliferations give it a subpinnate aspect. The calcareous 

 incrustation is light, mealy. The structure of the frond is that of 

 some members of the subgenus Goralia. The central cylinder is 

 very soft and in lime-free material the whole frond has a soft 

 mucous consistency. The central cylinder consists at first of closely 

 packed large cells with surrounding smaller filaments. At length 

 some of the smaller filaments appear to penetrate among the larger. 

 It is about 500 mic. in diameter in older parts of the frond, 100-200 

 mic. in the smaller branches. The cortical branchlets are some- 

 what stout, generally dichotomous at the summit of the basal cell 

 and at intervals upward, about 300 mic. long. The lowest cell is 

 cylindrical, emitting numerous small lateral filaments, the next cells 

 cylindrical, about 8x40 mic, the outer cells shorter, somewhat stout- 

 er, and more contracted at the ends, with gradual transition to the 

 outermost 3-4 cells which are short oval, forming the corymbose 

 summit and the terminal cell almost spherical, 7-9 mic. in diameter. 

 The cystocarps at first are plainly borne laterally near the end of a 

 cortical filament, but they soon come to appear terminal. The in- 

 volucre is composed of simple filaments or some with small abrupt 

 terminal fascicles. 



Ligaora Tildenii var. lubrica var. no v. 

 PLATE XXIV. FIG. 13. 



Fronde ea typi tenuiore, lubrica, 0.5-0.75 mm. lata crusta calcis 

 tenui pulverulente ; strato axile angusto, molli ; filis corticalibus in- 

 ferne inaequaliter dichotomis, superne corymbos ferentibus qui su- 

 per incrustationem calcis prominent. 



