1906] SHREVE—SARRACENIA PURPUREA . 123 
anatropous and there is a single integument. The megaspore mother 
cell divides to a linear series of four megaspores, or after the first 
division the micropylar nucleus may fail to divide or may Ve by 
a wall longitudinal to the ovule. 
3. The chalazal megaspore is functional, and develops a typical 
eight-celled embryo sac. The polar nuclei fuse and the endosperm 
may become two to eight-celled before the complete fusion of male 
and female nuclei in fertilization. 
4. The pollen tube grows through a definite conducting tissuc 
in the upper expanded portion of the style, through schizogenic 
canals in the stalk of the style and between the placental outgrowths 
in the ovary. The generative nucleus divides before the tube has 
passed into the stalk of the ovary. Fertilization presents no pecul- 
iarities. 
5. The embryo is elongated and straight, with cotyledons. The 
storage tissue is endosperm filled with aleurone. The seed coat is 
the external layer of the integument. The cotyledons function as 
haustoria in germination and survive as chlorophyl-bearing leaves. 
6. The first epicotyledonary leaf is pitchered and arises from a finger- 
like primordium in which a cavity is developed by unequal aati 
THE Woman’s COLLEGE OF BALTIMORE, 
Baltimore, Md. 
EXPLANATION OF PLATES III-V. 
Abbreviations used: ant, antipodal; arsp, archesporium; br, bract; cav, 
cavity; col t, columnar tissue; con c, conducting canal; con s, conducting strand; 
con t, conducting tissue; cot, cotyledons; cov, cover; cp, carpel; der, dermatogen; 
d s, dehiscing slit; e, egg; em, embryo; en n, endosperm nucleus; ¢ s, embryo 
BAG, GER, endosperm; f n, female nucleus; g , generative nucleus; im, integu- 
ment; int i, integument initials; J,.leaf; 1 p 0, lateral placental outgrowth; meg 
megaspore mother cell; meg sc, megaspore sister cell; mic mc, microspore 
testes cell; micsp, ha, ascent mn, male nucleus; m p 0, main placental 
outgrowth; uc, nucellus; ovary; par c, parietal cells; pet, petals; pn, 
polar nuclei; pi, initials of :sscstibee and plerome; pro c, procambium cells; 
Sc, seed coat; sep, sepal; st, stamen; stg s, stigmatic surface; stk, stalk of 
Style; sus, suspensor; syn, synergid; tap c, tapetal cells; im, tube nucleus; um, 
umbrella of the style; w, wing. 
All figures are camera drawings fom microtome sections except jigs. 29, 30, 
5°; 55, and 62, which are from free-hand drawings. 
