CALAMODENDRON. 25 



axis and an irregular zone of larger tubes, from which zone project six angular arras, that 

 appear to me to be transverse sections of six of the processes which support the sporangia, 

 and which it will be well hereafter to term "sporangium-bearers." These seem to 

 have been composed of tubes, having something of a pseudo-vascular character ; and the 

 lowest one in the figure appears to join with the outside covering of the bladder or bag 

 {/c Ic) containing the sporangia ; but of this we cannot be certain, as the parts of the 

 specimen are much disarranged. 



These two transverse sections (PI. IV, figs. 1 and 2), which are the best preserved 

 amongst many in my collection, afford us evidence that the central axis or column of 

 the cone was composed of hexagonal and pentagonal tubes, surrounded by a substance 

 which has left no evidence of its structure, and outside this is the zone of hexagonal 

 coarser tubes from which spring six heart-shaped bags or bladders containing the upper 

 twelve of twenty-four sporangia, similar to those described by Ludwig, except that their 

 number is two more than were seen in his specimen. 



% G. Description of Specimens (Cones of Calamodendron commune) Nos. 7 — 11. 



Plate V, figs. 1—5. 



Plate V, figs. 1, 2, 3, 4, 5, 5«, and 5^ represent the specimens, Nos. 7, 8, 9, 10, and 

 11, and are longitudinal sections of small cones similar to those (Nos. 5 and C) of which 

 transverse sections are given in Plate IV, and described at pages 23 and 24. 



Pig. 1 (No. 7) represents a specimen one third of an inch in length, and magnified 

 thirteen and a half diameters. It shows seven receptacles, or cells for sporangia ; and 

 more may have existed in the original specimen, as the| extremities of the cone 

 are probably wanting in the section. The bases or pedicles of the scales belonging to 

 the second and third receptacles (from the top) are seen to proceed on each side from 

 the central axis, and appear to consist of tubes or utricles, whilst the other divisions or 

 floors, four in number, which are cut outside the central axis, are concavo-convex, and 

 appear to be composed of a thick band of cells, whence spring the stout, fleshy, outside 

 scales or leaves, which take a vertical direction, and enclose each receptacle until the 

 bottom of the next scale or leaf is reached. In each receptacle is seen evidence of spo- 

 rangium-bearers, one opposite the other, springing from the central axis. In the upper- 

 most chamber is a tangential section of one ; in the 2nd, a similar section of two ; in the 

 3rd, a longitudinal section of two, which are seen to proceed from the central axis ; the 

 4th, a tangential section of two ; the same in the 5th. In the Gth is a tangential section 

 showing four sporangia grouped round a sporangium-bearer ; and this affords us distinct 

 evidence of the quadrate arrangement of the sporangia around the " bearer," as first 

 noticed by Ludwig. In the 7th and last receptacle, shown only on the outside of the 

 central axis, no evidence of a longitudinal section of a sporangium-bearer is seen, but a part 

 of one and larger portions of the terminal parts of four other scales or leaves are shown. 



4 



