CHAP. !!► 
SEED. 
245 
The outer integument is either membranous, coriaceous,’ 
crustaceous, bony, spongy, fleshy, or woody; its surface is 
either smooth, polished, rough, or winged, and sometimes is 
furnished with hairs, as in the cotton and other plants, which, 
when long, and collected about either extremity, form what is 
called the coma (sometimes also, but improperly, the pappus). 
It consists of cellular tissue disposed in rows, with or without 
bundles of vessels intermixed : in colour it is usually of a 
brown or similar hue : it is readily separated from the inner 
integument. In Maurandya Barclayana it is formed of re- 
ticulated cellular tissue ; in Collomia linearis, some Salvias and 
others, it is caused by elastic spirally twisted fibres enveloped 
in mucus, and springing outwards when the mucus is dis- 
solved. In the genus Crinum it is of a very fleshy succulent 
character, and has been mistaken for albumen, from which it 
is readily known by its vascularity. According to Brown, a 
peculiarly anomalous kind of partition, which is found lying 
loose within the fruit of Banksia and Dryandra, without any 
adhesion either to the pericarp or the seed, is a state of the 
outer integument ; it is said, that in those genera the inner 
membrane (secundine) of the ovule is, before fertilisation, en- 
tirely exposed, the primine being reduced to half, and open 
its whole length ; and that the outer membranes (primines) 
of the two collateral ovules, although originally distinct, 
finally contract an adhesion by their corresponding surfaces, 
and together constitute the anomalous dissepiment. But it 
may be reasonably doubted whether the integument here 
called secundine is not primine, and the supposed primine 
arillus. 
The inner membrane (secundine) of the ovule, however, 
in general appears to be of greater importance as connected 
with fecundation, than as affording protection to the nucleus 
at a more advanced period. For in many cases, before im- 
pregnation, its perforated apex projects beyond the aperture 
of the testa, and in some plants puts on the appearance of an 
obtuse, or even dilated, stigma; while in the ripe seed ft is 
often either entirely obliterated, or exists only as a thin film, 
which might readily be mistaken for the epidermis of a third 
membrane, then frequently observable. 
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