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:MISS B. M. T3RIST0L ON 



describing the same species, and suggests tlie establishment of a new species, 

 Chlorocht/triuni lieinhardtii^ N. L. Gardner, to include the form described by 

 Reinhnrdt. 



This course seems to be somewhal" unnecessary, since Lngerlieim's amended 

 description of the species would certainly seem to support Reinlmrdt's 

 opinion that tlie two foi'ms were the same. Unfortunately, Reinhardt's 

 original paper has not been available for reference in this woi-l<, and my 

 conclusions have had to be based entirely on second-liand descriptions of the 

 alga ; Gardner, however, makes no statement of any definite characters by 

 which the identity of C Rehihardtii could be estiiblished, and without such a 

 statement, judging by the evidence at my disposal, his sotting up of this new 

 species seems to me to bo unjustified. 



C. CoiiMi, E. P. Writ>ht, var. PoRrTiYTi.E (Setchell & Gardner), nob- 

 Gardner has also described"^ what he considers to be a new species of Chloro- 

 chytrhnn under the name of C. PorpJnjnv, Setchell & Gardnor (1917), but his 

 diagnosis might apply with almost equal accuracy to the form described by 

 Lagerheim in 1884. The cells are spherical, 40-00/i in diameter, completely 

 imbedded within the host and with no small tubular projection on the cell-walb 

 Lagerheini's cells were more variable in shape than this, though many globular 



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individuals were found, and the^ were smaller, not usuallv exceedino; 40// in 

 diameter. The absence of a tubular projection cannot be regarded as of 

 specific importance, since Wright lias observed that individuals of C. Cohmt, 

 Wright, which are embinlded completely in the host-plant are similarly 

 destitute of a projection on the cell-wall. 



For the res^, Gardner's form contains a single cldoroplast, which is at first 

 small and covers only the upper part of the cell, but which later increases in 

 size by sending out several radiating arms, and finally lines the whole cell- 

 wall ; it contains a single pyrenoid embedded in the chromatophore toward 

 that part of the cell nearest to the epidermis of the liost. Successive 

 bipariition of the contents takes place with the formation of biciliate gametes, 

 all of one size, which escape through an oval aperture in the cell-wall. They 

 fuse in pairs to form quadriciliate zj^gotes which peuf^trate into the liost- 

 tissues as in Lagvrheim's form, except that no part of the germinating zy<i;ote 

 remains on the epidermis to make a neck-like prqp^ction. The tlescription 

 thus agrees almost exactly with that of Laoerheim, the slight diff 



erence in 

 the chloroplast being of neollniblc importance, while the absence of the 



tubular neck may be due to a diflercnce of host. It would therefore be 

 best to regard this at most only jis a variety of C. Cohm. Wright, differing 

 from it in being com[»letely embedded and in being destitute of a tubular 

 projection on the wall. 



* Univ. Calif, rubh in Botany, vol. vi. June 1917. 



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