354 FOURTH GROUP. SEED-PLANTS. 



peculiar anther proceeds from the floral axis itself 1 ; it has two annular locula- 

 ments, an upper and a lower. Since the rest of the Cucurbitaceae have distinct 

 staminal leaves of the normal form, comparative morphology considers the one anther 

 of Cyclanthera as formed of five anthers completely fused together, though there are 

 none but phylogenetic reasons for this view, there being no visible signs of any such 

 amalgamation. The four loculaments of an anther are simply sporangia sunk in the 

 swollen tissue of the anther 2 , and their development agrees perfectly in all points with 

 that of the microsporangia of the Gymnosperms and of the sporangia of the Equi- 

 setaceae and Lycopodieae 3 . Two loculaments are formed in the anterior and two in 

 the posterior angles of the young stamen ; but the position of the loculaments is often 

 different from this in the mature state of the stamen ; either two are lateral on the 

 stamen, and two are on its dorsal side, that is, the side towards the floral axis, or the 

 loculaments all appear to belong either to the dorsal or to the opposite and ventral 

 side. Displacements of this kind are caused by subsequent processes of growth in 

 the young anther, especially in the region of the connective 4 . Anthers in which the 

 loculaments are turned outwards are said to be extrorse, as in Aristolochia, Tamarix, 

 and Iris, those with loculaments turned inwards are introrse, as in Cypripedium and 

 Nuphar. Before proceeding to the consideration of the pollen-sacs and their 

 contents, we will return for a moment to the subject of the entire stamen and the 

 androecium. The stalk or support of the anther (the filament with the connective) is 

 either sirnple or articulated; the simple stalk may be filiform (Fig. 269), or dilated 

 and leaf-like (Fig. 268 D\ or sometimes even very broad, as in the Asclepiadeae and 

 Apocynaceae, or it is enlarged below (Fig. 275^") or above; it usually terminates 

 between the two anther-lobes, but is sometimes prolonged above them (Fig. 268 D) 

 as a projecting point or in the shape of a long process, as in Oleander. If the upper 

 part, the connective, is broad, the two anther-lobes are distinctly separated (Fig. 268, 

 274); if it is narrow, they lie close together. The articulation of the filament is very 

 frequently due to the sharp demarcation of the filament from the connective by a 

 deep constriction ; the connection is kept up by so slender a piece of tissue that the 

 anther and connective together oscillate and turn freely on the filament (versatile 

 anther] ; the point of attachment may be at the lower or upper end or in the middle 

 of the connective (Fig. 275); sometimes the connective attains a considerable size 

 and forms appendages beyond the anther (Fig. 276 A, x)> or it developes as a cross- 

 bar between the two anther-lobes, so that filament and connective form a T., as in 

 Tilia and still more notably in Salvt'a, in which the transverse connective has only a 



1 Warming, Ueber pollenbildende Phyllome u. Caulome in Hanstein's Abh. II. Bd. I. Engler, 

 Beitr. z. Kenntn. d. Antherenbildung d. Metaspennen (Angiospermen) in Pringsheim's Jahrb. f. wiss. 

 Bot. x. p. 275. 



2 It is necessary therefore in dealing with the anther to distinguish carefully between the tissue 

 of the stamen (the sporophyll) and the microsporangia ; the old explanations, which were founded 

 on malformations and are now obsolete, often enough neglected this distinction, though the right 

 conception is to be found in Cassini and Roeper. In malformations (phyllomorphy, frondescence) 

 we get the stamen in different states according to the stage of its development at the time that it 

 experienced the metamorphosis into a vegetative leaf, and these states, though very interesting in 

 themselves, have given occasion to some absurd notions. 



8 See Goebel, loc. cit., on page 325. 

 * Warming, loc. cit. ; Engler, loc. cit. 



