Linnaan Society. 311 



in the West Indies, while all other species of Myoporacece are 

 found in Australia, in Asia, or in the islands of the Paciiic bordering 

 on that continent. 



The author next proceeded to indicate those points of structure in 

 Oxycladua which establish the relative value of its affinity to the 

 Myoporacece, or the Bignoniacece. In this genus, both the branches 

 and rudimentary leaves are distinctly opposite, as in Bignoniacece, in 

 which family we find two other genera, where the branches terminate 

 in spines, viz. Catophractes and Rhigozum : the flowers are bluish, 

 a colour not met with in Myoporacece ; they present a sterile fifth 

 stamen, a circumstance almost constant in Bignoniaccce, and never 

 seen in Myoporacece; the anther-cells are distinct, and widely divari- 

 cated upon a large fleshy connective, as in Bignoniacece, not oscil- 

 latory, lunulate, and opening by a hippocrepiform fissure, and there- 

 fore almost one-celled, as in Myoporacece; the ovarium is seated upon 

 a five-lobed fleshy disk, which never occurs in the latter family, though 

 constant in Bignoniacece ; it is completely bilocular, with about six 

 ovules in each cell, suspended and attached by a ventral thread to a 

 distinct flat dissepiment, and arranged in three superimposed pairs 

 upon its opposite faces, in two lines parallel with the axis, a structure 

 which offers a marked character in the Bignoniacece, and unknown 

 in the Myoporacece ; of these twelve ovules, all become abortive 

 with the exception of one ; the fruit is therefore 1-locular and mo- 

 nospermous, presenting an osseous nut, with four deep furrows in 

 the apex, and divisible to the base along these striae into four valves, 

 two of these sutures being more easily separable, and always corre- 

 sponding with the margin of the persistent dissepiment, which is 

 pressed against one side, and which distinctly exhibits on both faces 

 its several abortive ovules, the ripened seed filling the whole capacity 

 of the nut. In Myoporacece, whether the nut be 4-celled, or by abor- 

 tion 2-locular, the intervening space is always solid, and perfectly 

 indehiscent, leaving small circular cells, surrounded by thick 

 ligneous walls, without showing any marks of division ; there is no 

 analogy whatever between this structure and that of Oxycladus. 

 The absence of the alary expansion of the testa, so common in 

 Bignoniacece, is urged as a reason for excluding this genus from that 

 family, but the argument is not valid, where as in Oxycladus only 

 one of the ovules becomes impregnated, and where it is thus left at 

 full liberty to acquire the size and shape of the whole space of the 

 cell. The want of wings in the seeds occurs however in other 

 Bignoniaceous plants ; for instance in Spathodea of Palisot de 

 Beauvois, from which all the species from the New World referred 

 to that genus have been rightly separated by Chamisso under the 

 name of Dolichandra. Mr. Miers has also found in Brazil another 

 Bignoniaceous genus, Adenocalymna, the carpological characters of 

 which are yet undescribed, which has a cylindrical, capsular, 2-celled 

 fruit, containing several large, thick, angular seeds, attached by a 

 large hilum to the broad dissepiment, and without wings. In 

 Argylia the seeds are likewise apterous. The last consideration as 

 regards Oxycladus is not the least important ; its seeds are exalbu- 



