46 Henderson — Comparative Study of Pyrolaceae and 



four exterior cells surrounding a central large one." The writer 

 examined material of Newberrya spicata A. Gray and N. con- 

 gesta (A. Gray) Torr. and found an exactly similar condition 

 to that in the rest of the family — i.e., that the ovary at the base 

 is five-celled owing to the fusion of the placentae and that 

 owing to a lack of fusion further up the ovary became one-celled 

 with parietal placentae. Pleuricospora fimbriolata A. Gray 

 shows the most simplified condition in regard to the ovary. 

 It is four-celled only at the very base for about one-sixth the 

 distance, then one-celled with four parietal placentae. 



(2) In typical Ericaceae the seed is very small, never larger 

 than 1-2 mm. The seed covering is double, there is a richly 

 developed endosperm in which is embedded a straight embryo 

 which is one-third to two-thirds the length of the seed. The 

 embryo always shows a root, an axis, and two cotyledons. The 

 seeds in the Rhododendroideae-Ledeae, the tribe nearest in 

 character to the Pyrolaceae, are winged, very small, and con- 

 tain a very small embryo. These seeds are very similar to 

 those of the Pyrolaceae, except that in the latter the embryo 

 itself is very much smaller, simplified to a few cells, and with 

 no differentiation into root or cotyledons. The amount of 

 albumen in which the embryo is embedded is also reduced. 



(3) There is in practically all typical Ericaceae, at the base 

 of the ovary, a nectar-secreting disc which may be present 

 as a circular ring or a crenulately lobed swelling. M tiller has 

 illustrated those of Arctostaphylos, Calluna, Erica, Azalea, Rho- 

 dodendron, and Warming those of Andromeda, Cassiope, Phyllo- 

 doce, in Knuth's "Handbook of Flower Pollination" (42). Drude 

 (12) seems to indicate that it is lacking in the Pyrolaceae and 

 Monotropaceae and gives this as a reason for separating them 

 from the Ericaceae. In C. umbellata and C. maculata it is 

 present as a nectar-secreting ring at the base of the ovary. In 

 the genus Pyrola the disc varies. According to Drude (12) it 

 is present as a ten-rayed nectar-secreting organ in P. (Moneses) 

 uniflora, but Miiller (42) states that there is no nectar secreted 

 by M. uniflora and figures no nectaries. The writer sees no 

 trace of nectaries in the material examined. Drude states 

 that the disc is present as ten small nectaries at the base of the 

 ovary in P. secunda and is absent or rudimentary in all of the 

 other species. The writer found very small swellings that 



