42 
CONTRIBUTIONS TO BOTANY. 
the albumen, I find constantly, midu’ay between the axis and 
this groove, and imbedded in the substance of the albumen, a 
very distinct, long, cylindrical, membranous tube, which proceed- 
ing from the base terminates abruptly, by an almost truncated 
closed apex, at about half the length of the seed; the lower 
portion, at its exit, is reflected upwards round the base, for a 
short distance, in a small groove, and is soon gradually lost in 
the substance of the enveloping integument. We cannot imagine 
this tube to be anything else than the posterior end of the em- 
bryonary sac, which in Osyris Mr. Griffith describes as becoming 
incorporated with the nascent albuminous tissue, but which here 
appears to remain entire, and its existence in the position above 
described can only be accounted for by supposing its reduplica- 
tion during the development of the albuminous tissue. On 
dividing the putamen, the albumen will be found quite bare of 
any integumental covering, except at the lacerated margin of 
the cionosperm, around the hollow space at the base, and about 
the summit, where it has broken away from the abortive ovules, 
which as well as the cionosperm become entirely pressed into 
the substance of the albumen : the rest of the extremely thin 
integumental covering remains adhering to the inner surface of 
the putamen ; but whether the external body of the ovide becomes 
withered and contracted into the substance of the cionosperm, or 
whether its induvial remains are to be referred to the quantity 
of colourless, dislocated tissue found between the adherent mem- 
branes that form the lining of the putamen and the seminal in- 
tegument, it is impossible to determine from an examination of 
dried specimens. 
Besides the knowledge of the singular fact of the exsertion of 
the embryonaiy sac, and the development of the embryo outside 
of the body of the ovule, common to the Santalacete, and by 
analogy to the Olacacece and other Cionospermce, that of the 
confluence of the albumina of several sacs into one albumen is 
stated to occur in Viscum album : this however is not quite a 
manifest explanation of the pluenomenon, for if these were con- 
fluent, the embryos would not unite at base, but would remain 
distinct, by the intervention of the confluent sacs, unless we 
imagine these membranes to become absorbed into the substance 
of the nascent albumen. Dr. i\Ieyen, on the contrary, denies 
the fact so minutely described by i\l. Decaisne, in the memoir 
before quoted, of the growing together of several embryos ; for 
he asserts, that several embryouary sacs are contained in a single 
ovule, and are fertilized, but it rarely happens that more than 
one of these arrives at perfect development*, and he therefore 
concludes, that the doubling or trebling of the radicular end of 
* Ann. Nat. Hist. Ser. 1. vii. p. 171- 
