MR. W. GRIFFITH ON THE GENUS GNETUM. 311 



exserted portion of the tubular prolongation. The prolonged apex of the outer coat (a) is distinct, 

 as well as the formation of the large yellowish fibres. The second coat (b) has become thicker 

 towards its apex, and somewhat indurated. The inner or additional coat (c) is now adherent to 

 the nucleus throughout the greater part of the extent of this latter organ. That part of it which 

 corresponds to the constricted apex of the nucleus is thickened ; its prolongation is considerably 

 dilated after it has passed through the narrow, and now cylindrical, tubular perforation ot tht 

 second coat. The excavation is large, and its margins are rugged and more or less blackened. 



Fig. 22. Vertical section of an ovule of G. scandens ; the nucleus is surrounded inferiorly by the two outer 

 coats ; the notch on either side (a, a) indicates the place of separation of the additional (third) coat. 

 The cavity is much enlarged, and occupied by a clavate body, of which the outline is given in 

 the adjoining figure 23. 



Fig. 23. Body occupying the uucleary cavity ; this is the rudiment of that which subsequently becomes 

 the very copious fleshy albumen. 



Fig. 24. Vertical section of a full-grown fruit of G. apiculatum, in which, however, no embryo had been 

 developed : a. outer baccate coat, the inner half of which is composed of very large fibres ; 

 these are of a yellowish colour, shining appearance, and imbedded in a reddish-yellow pulp : 

 b, b. drupaceous covering ; c, c, c. inner or additional coat, with its woody, fragile, enclosed and 

 prolonged apex (to this the fourth coat adheres firmly, except at its sphacelated apex, d) ; 

 e, albumen, now copious and fleshy, by the great development of which the original nucleus has 

 become reduced to a thin membrane, of which the free apex is seen at rf; /. excavation at the 

 apex of the albumen occupied by broken-up tortuous tissue, the rudiments of a funiculus. The 

 direction of the subsequently-extended excavation may be traced lower down, and is indicated by 

 a greater density of texture than occurs elsewhere. 



Fig. 25. Albumen of the same detached, viewed on its entire surface : at d. is seen the apex of the nucleary 

 membrane with its sphacelated apiculus. 



Fig. 26. Vertical section of the same, showing the cap which the adhering apex of the fourth or nucleary 

 membrane makes for it. The tortuous tissue is visible in the cavity. 



Tab. LVI. 



Fig. 27. Considerably advanced ovule of G. Brunonianum ; vertical section. 



Fig. 28. Vertical section of a mature and, with the exception of the embryo, fully -formed seed of G. scan- 

 dens : a, a, a. the outer coat, which has become pulpy and baccate, the fibres lying rather loosely in 

 the pulp ; it is perforated by the prolonged persistent apex of the third covering (c) ; b, b, b. the 

 second or drupaceous coat, shown to consist of two layers also perforated at the apex ; c, c, c. the 

 third membrane, composed of the additional and nuclear membranes ; these are united except 

 at their apices, — the apex of the nucleary membrane always separating with the albumen, and 

 forming for it an irregular lacerated cap ; d. albumen ; e. the central apical cavity, empty. 



Fig. 29. Vertical section of an immature seed of G. apiculatum: a. outer coat; b. second coat; c. nucleary 

 membrane of albumen ; d. albumen ; e. sphacelated apex of albumen ; /. apical cavity ; ff. tortuous 

 suspensor lodged in ditto. 



Fig. 30. Tortuous suspensor (g) in fig. 29 extracted and highly magnified. 



Fig. 31. Vertical section of the separated albumen of a similar seed. 



Fig. 32. Vertical section of the albumen with its cellular attachment ; showing the embryo in situ and its 

 lateral attachment. 



Fig. 33. Embryo and funiculus extracted and highly magnified, showing the lateral attachment. 



Fig. 34. Embryo with the apex of the funiculus ; the cotyledons are seen to be remarkably small and 

 equal. 



