GYMNOSPERMAE.— CONIFER A E. 329 



cushion in ihe middle of which a protuberance is soon apparent which subsequently 

 developes into a stalk ; this stalk may be seen in Fig. 257 A, on the anterior side of 

 the seminiferous scale between the macrosporangia. The lobes of the young scale 

 swell up on both sides of this elevation, and on them the macrosporangia are formed. 

 These appear as flat protuberances, and are each surrounded at once by a distinct 

 two-lipped wall, the rudiment of the integument. The seminiferous scale now grows 

 chiefly on its upper and outer margin, so that the keel comes to be on the inner face 

 of the scale (Fig. 257); but some growth also takes place in the region of insertion 

 of the macrosporangia, so that these as they develope are completely gird round with 

 the tissue of the scale and partly adhere to it (Fig. 257 sk). Thus the micropyles of 

 the macrosporangia or ovules are turned towards the axis of the cone. The semini- 

 ferous scale in this species has a special system of vascular bundles distinct from that 

 of the bract-scale, while the smaller outgrowths on the bract-scale of Araucaria for 

 example only receive a branch from the bundle which enters the scale ; we shall 

 recur to this point further on. 



In the Cupressineae the macrosporangia are on a slight swelling in the axils of 

 scales, which are arranged in whorls containing two or more members and are united 

 together in comparatively small numbers to form a diminutive cone. There is no 

 seminiferous scale here as in the AbieUneae ; the scales of the cone at flowering time 

 diff"er but little from vegetative leaves, but after fertilisation they grow vigorously and 

 reach a considerable size. They cohere and envelope the seeds, and thus form a 

 fleshy or dry fruit which is developed differently in the different genera. In Biota 

 on'enlalis the cone is formed of three decussating pairs of scales, of which the two 

 lower pairs only are fertile, the upper ones having no macrosporangia in their axils. 

 The cones occupy the extremities of short lateral branches of the same year, and 

 the scales bearing macrosporangia are fully developed when the first rudiments 

 of the sporangia make their appearance. The macrosporangia are formed on a 

 slight axillary protuberance, singly on the lower scales, on the upper in pairs. In 

 the succeeding spring the scales and the axillary protuberance begin to enlarge 

 immediately above the insertion of the macrosporangia, and a dark-coloured wall is 

 formed at the base of the scale which swells up so considerably, that the apex of the 

 scale when the cone is matured appears to be inserted beneath this enlargement, 

 which is more or less distinctly separated from the scale (Fig. 256, 7, 8). The small 

 cones o{ Juniperus commmiis (Fig. 253 C) consist of three scales, which form a whorl 

 of three members beneath the naked extremity of a small shoot springing from the 

 axil of a foliage-leaf. In the axil of each scale is a macrosporangium, not in front 

 of the centre of the scale but on one side of it, so that the three macrosporangia 

 (ovules) appear to alternate with the scales. The scales swell after fertilisation, 

 cohere as they grow and become fleshy, and form the soft substance of the blue 

 berry in which the ripe seeds are completely enclosed. In Jtmipcrus Sabina also the 

 fruit is like a berry; in other Cupressineae {Thuja, Cupressus, Ca//i/ns) the scales 

 together with the enlargement subsequently formed become woody, and develope into 

 stalked shields or into valves, as in Frcnela, the lateral margins of which approach 

 one another and remain closely joined during the development of the seed, but after- 

 wards separate to allow the ripe seeds to fall out. \n Juniper us Sabina and Callitris 

 quadrivalvis (Fig. 258) there are only two decussating pairs of scales which separate 



