228 



On examining the black markings of C. pandiirata under the 

 microscope and in sections, I found that they were entirely 

 superficial, situated on innumerable closely placed small papillae. 

 By transmitted light they appear brown, and the cinnamon 

 color of the basal depression is doubtless due to the same pigment 

 in dilute form. The pigment gives none of the anthocyanin 

 reactions, nor does it look like anthocyanin. It is soluble in 

 strong alkaline solutions, and produces a cherry-colored liquid. 

 This readily stains paper, but does not change color on drying. 

 Acid almost entirely discharges the brown color. I am indebted 

 to Dr. F. Ramaley for the suggestion that the reactions resemble 

 those of turmeric, derived from Curcuma (Zingiberaceae). The 

 pigment in turmeric is curcumin, CuHieOy. It seems evident 

 that Coelogyne possesses a . closely related though doubtless 

 distinct pigment. Even in species such as C. speciosa and C. 

 asperata, in which the lip is marked with red or cinnamon, there 

 is probably no anthocyanin at all. Pfitzer and Kranzlin remark 

 that blue or blue-violet colors are lacking in the whole tribe 

 Coelogyninee, but the genus Pleione, to judge from the descrip- 

 tions, must certainly possess anthocyanin. 



In the case of Coelogyne sparsa Reichb. f., Ames* quotes a 

 collector to the effect that the flowers are white with lavender 

 spots. This would suggest anthocyanin, but it must be an error, 

 as others found the markings to be light brown or purplish 

 brown. 



Boulder, Colorado 



BOOK REVIEWS 



Rock's Lobelioideae of Hawaii t 



The flora of the Hawaiian Archipelago has long been known 

 as one of the most peculiar in the world, not alone for its fan- 

 tastic forms of relatives of well known plants, but for the large 

 number of species that are endemic there. Its isolation is so 



* Orchidaceee, fasc 2, p. 70. 



t Rock, J. F. A Monographic Study of the Hawaiian Species of the Tribe 

 Lobelioideae, Family Campanulaceae. Pp. I-XVI + 1-394- 217 full-page 

 plates. Publication of the Bernice Pauahi Bishop Museum. Honolulu. 20 

 February, 1919. 



