4 Mr. J. Miers on the Menispermaceae, 



is sometimes valvate^ as in the cases last mentioned : this occurs 

 in Tiliacora, Ahuta, and Limacia. The symmetry in the arrange- 

 ment of the floral envelopes, though generally similar in both 

 sexes, does not exist in Cissampelos, Cyclea, Clypea, Antizoma, 

 and Stephania, where, in the female flowers, many of the parts 

 are wanting, being sometimes reduced to a single sepal and only 

 one minute petal, while the male flowers exhibit the usual num- 

 ber of sepals. 



The petals, usually six in number, are in the form of small 

 scales or fleshy leaflets originating from the torus. Little notice 

 was taken of them formerly, as they were looked upon as a mere 

 nectary ; but they are now universally regarded as real petals, 

 though of minute size; in some few instances they are en- 

 tirely wanting, as in Abuta, Anelasma, and Batschia : in Fi- 

 hraurea they are apparently deficient, but they are probably con- 

 fluent with the filaments, seemingly as if wrapped round them : 

 in many of the genera the petals, though quite free, are found, 

 in a similar manner, with their margins involute and embracing 

 the filaments. 



The stamens, especially in the male flowers, by their form and 

 position, afford constant and valid characters ; they are usually 

 equal in number to the petals, opposite to them, and generally 

 in two distinct approximated whorls. In most instances they 

 are all quite free; but sometimes the three outer stamens are 

 free, while the others are partially monadelphous in the centx-e ; 

 at other times they are all more or less compactly united into a 

 simple central column. They are usually as long as the petals, 

 frequently double their length. The anthers are generally two- 

 lobed, the lobes being often separated by a connective, which is 

 continuous with the filament; sometimes they are combined to- 

 gether without the intervention of any connective, and partially 

 sunk in the apex of the filament, or often approximated and 

 dorsally affixed upon it ; generally these lobes open by a longi- 

 tudinal suture, but they sometimes burst by a transverse, verti- 

 cal, or oblique 'fissui'e. In the Cissampelos group, the stamen 

 consists of a single filamentous column supporting a horizontal 

 peltate disk bearing on its margin four, six, eight, or more 

 anther-cells, combined in an annular form, which burst on their 

 outer edge, like the indusium of some ferns. In other cases 

 several anther-cells are combined into a globular mass, and are 

 either sessile on the torus or supported on a central column. 

 In many cases each anther-cell appears bilocellate, owing to a 

 prominent septum that almost or completely divides it. These 

 great varieties in the disposition and structure of the stamens 

 are constant in each genus, and may be trusted as good discri- 

 minating characters. 



