Grew enters into considerable detail as regards the structure of flowers, and it is only possible to mention here a few of the points to which he draws attention. He observed the frequent occurrence of capitate glandular hairs, which he describes as "like so many little _Mushrooms_ sprouting out of the _Flower_," their heads sometimes exuding a "_Gummy_ or _Balsamick Juyce_." He describes the varieties of aestivation of the floral leaves, and notes that, in the Poppy, the large size and fewness of the petals prevents their being folded into a compact body by any of the ordinary methods. "For which reason, they are cramb'd up within the _Empalement_[16] by hundreds of little _Wrinckles_ or _Puckers_; as if Three or Four Fine _Cambrick Handcherchifs_ were thrust into ones _Pocket_." We have said something about Grew's work on seeds, in dealing with his first treatise. He was always much interested in this subject, and returned to it again in his later work. He mentions the mucilaginous testa possessed by many seeds, but which only becomes noticeable when they have been moistened. That of "_Nasturtium Hortense_" he describes as very large, "even emulous of the inner Pulp surrounding a _Gooseberry-Seed_." He suggests that the value of putting a Clary seed into the eye to bring out a foreign body, which may have lodged there, is due to the presence of the mucilaginous coat. The same seed is still, I believe, used for this purpose, under the name of "eye seed." Grew understood the difference between seeds with, and without endosperm, and gives perfectly clear representations of such albuminous seeds as _Ricinus_. He describes the cotyledons of the Dock as being immersed in the endosperm, "as in a _Tub_ of _Meal_ or a little pot of pure refin'd _Mould_, necessary for the first _Vegetation_ of the _Radicle_." Grew naturally reckoned the spores of Ferns among seeds. The seed-case of the Harts-tongue is, he says, "of a _Silver Colour_ ... of a _spherick Figure_, and girded about with a sturdy _Tendon_ or _Spring_, of the _Colour_ of _Gold_: ... So soon as ... this _Spring_ is become stark enough, it suddenly breaks the _Case_ into two halfs, like two little _cups_, and so flings the _Seed_," of which "ten Thousand are not so big as a white _Pepper Corn_."