NATURAL HISTORY SOCIETY OF GLASGOW. 35 



a very doubtful relationship between the Permian Synocladia and 

 those Carboniferous forms placed in the same genus. On the other 

 hand, the Permian Thamniscus presents us with several external 

 characters, in its foramina amongst the cells of the poriferous face, 

 as well as in having scattered foramina all over the reverse face — 

 according to Prof. King — which relate it very closely, in the ar- 

 rangement of its cell structure, to that of the Carboniferous forms 

 doubtfully placed with Synocladia. It would, therefore, be very 

 desirable that there should be a careful examination of well-preserved 

 specimens of the Permian and Carboniferous forms, for the sake of 

 ascertaining correctly, in what respects the Permian Synocladia and 

 Thamniscus differ or agree with the Carboniferous forms. I sin- 

 cerely hope that some palaeontologist interested in the group, who 

 is able to examine well-preserved specimens from both formations, 

 will be induced to take the question in hand, and clear up those 

 doubtful points in their relationship. 



II. — On the structure of an Orange. By Mr. Thomas King. 



After some introductory remarks, the writer said that Goethe's 

 theory of morphology — that in a flowering plant there were only 

 two kinds of organs, viz., stem and leaves, modified in many ways — 

 was now generally regarded as a sound one. That the sepals and 

 petals of a blossom are leaves is plain enough. The stamens are not 

 ordinarily leaf-like, but they are also foliar organs, as is shown in 

 the cultivated rose, where they are transformed into petals. The 

 pistil is also a foliar organ, as is seen in a monstrous state of the 

 cherry tree — the pistils, which in ordinary circumstances would 

 have developed into cherries, merely become leaves. The pistil is 

 composed of one or more leaves, each of which is called a carpel. 

 Some are formed of a single carpel, as in the pea ; others of several, 

 as in the lily ; and we are generally able to tell the number of 

 carpels in any pistil from the number of styles surmounting the 

 ovary, or from the cavities it contains. The axis, or stem, on which 

 the foliar organs of the flowers grow was next considered. The 

 extremity of the axis is called the tones, or receptacle ; it is an axial 

 root or foliar organ. In most flowers it presents a rounded or flattened 

 appearance ; while in others, such as the rose hip, which is the 

 extremity of the flower stalk, it is hollowed out into a cup, which 



