306 I'HirosopHiCAr. notes on 



the parental stem.* If the seed-bud or phiiimle is a branch and 

 homologous with any other branch, it will necessarily follow that 

 it is also homologous with the stem of a grass, a sedge, a horsetail, 

 an orchid, &c. Then very probably the primine and secundine of 

 the seed will find their homologues in the leaf-sheath of the horse- 

 tail, or the vagina of the sedge and orchid leaf, the blade of the 

 latter being suppressed. Imagine the seed to remain attached to 

 its parent and growing into a branch, and you have the two inte- 

 guments falling into their proper places as two of the leaf-sheaths 

 of the liorsetail, with the interno<le suppressed. 



Fourteenth. — The hairs of plants are the most interesting part, 

 from an evolutionary point of view. I look upon them as 

 atrophied reproductive organs of various forms. They have been 

 o-iven various names by botanists, and have been considered as 

 unimportant epidermic emergences. Nevertheless, there is no 

 part of the plant which cannot l)e and is not sometimes reduced to 

 the level of an epidermic hair, without any vascular tissue. The 

 root, the stem, the leaf, the pinna^, the stipules, the axillary bud, 

 the sepal, the petal, the stamen, the carpel, the ovule, all can be 

 atrophied into hairs. The terminations of the branches of Rhus 

 cotinus, or its racemes, are nothing but a conversion of peduncles 

 into hairv endings, w^ith the flowers suppressed. Now and again, 

 at the apex of a hairy peduncle, there is a floret. The atrophied 

 ))ranches of this Rhus correspond to hairy rootlets. The glandular 

 branched coverings of the stem and sepals of the moss-rose, and 

 the teeth of its leaves, are only branched hairs, developing 

 foliaceous stems. There can be little doubt that they correspond 

 morphologically to the variously shaped branches which are to be 

 found on the external surface of seaweeds. In the higher plants 

 these hairs are remnants of important reproductive organs, derived 

 directlv from the lower plants, and therefore must be homologous 

 with them. In the animal kingdom their analogues would be the 

 splint bones of the horse, which are remnants of once useful 

 digits. 



Fifteenth. — The fig is obviously a further development of a 

 conceptacle of a Fucus or other seaweed. And there is every 



♦When the stem decays, or when the buds drop off, they also become 

 temporary stores of nutriment. 



