220 Mr. A. Murray on the Floral Homologies of Conifers. 



of the scale, it is in reality allotted wholly to the inner half of 

 the scale. Fig. 14 shows the apophysis of the scale in Welling- 

 tonia, fig. 15 a section of a scale taken from a mature cone of 

 that speciesj and fig. 16 a section of a scale of Pinus patula ; 

 and it will be seen that the posterior ligneous plate in both cuts 

 in with rather an abrupt turn just behind the raucro. It would 

 appear therefore as if the greater strength was apportioned to 

 the inner portion of the structure rather than to the outer, 

 which is just what we find in other nuts, such as the cocoa-nut, 

 &c. 



2. The Wing and Envelopes of the Seed. 



I assume, then, as a fact already proved, that the covering of 

 the seed of which the wing is part is the carpel. In discrimi- 

 nating its different parts, the only difficulty is with regard to 

 the mesocarp. The testa is, of course, the endocarp, equivalent 

 to the stone of the peach or to the pip of the cherry. The wing 

 is equally, of course, part of the epicarp. It is double, and, as 

 already said, usually covers one side of the seed entirely, and 

 more or less of the other side. In the firs, and especially the 

 silver firs, it is folded like a sheet triangularly round the seed, 

 leaving a portion at each end more or less exposed. There is, 

 however, not much mesocarp ; but if the wing in some species 

 be cut across immediately above the seed, a moderate thickness 

 of cellular substance will be found there. This I consider the 

 mesocarp, which thins off on either side. 



Within the carpel are found, in Conifers as in other plants, 

 the ovule, consisting of a nucleus enclosed in its two coverings, 

 the primine (the outer) and the secundine (the inner), as diffi- 

 cult to distinguish as in other plants, but not more so; and the 

 tercine, quartine, and quintine of Mirbel, representing respec- 

 tively the albumen of the cotyledons, the circumvolution of the 

 embryo-sac, and the embryo-sac itself, are, of course, there too. 



There remains to say one word, and only one, upon the cor- 

 puscles in the ovule. It appears to me that their significance 

 has not been fully apprehended. The corpuscles or embryo-sacs, 

 rightly taken, are the young cotyledons; and to say that an 

 ovule has only two cotyledons is merely saying in other words 

 that it has only one embryo-sac ; or to say that it is polycoty- 

 ledonous, is equivalent to telling us that it has corpuscles in 

 the ovule. Brown says upon this point, " that each of these . 

 opaque bodies terminating the trunk and branches of the funi- 

 culi are really rudimentary embryos, is proved by tracing them 

 from their absolutely simple state to that in which the divisions 

 of the lower extremity become visible, and those again into the 

 perfect cotyledon^' 



