687 



Sub-Class IV. EPIGYNOUS EXOGENS. 



In general the complete adhesion of the tube of the calyx to the ovary 

 through its whole length, and the bisexual flowers, afi'ord a positive mark 

 of distinction for this Sub-Class, which is undoubtedly composed of Orders 

 which form perfectly Natural Alliances, closely related to each other, but 

 indicating very strong lateral affinity for other parts of the system. Thus 

 Campanals approach both Bignonials, in which Gesnerworts have a half- 

 inferior ovary, and Solanals, among which Jaborosa has the stamens almost 

 free from the corolla ; Myrtals lean towards Rosals, whose flowers are 

 furnished with a half-inferior ovary in the Order of Appleworts ; the 

 frontier of Grossals joins that of Saxifragals, the Currantworts of the one 

 very nearly agreeing with the Cunoniads of the other ; Umbcllals are com- 

 pletely imitated by Thalictrum among the Crowfoots of the Ranal Alliance, 

 and by Vitaceae among Berberals ; and finally, the Asaral Alliance has its 

 analogy in Helwingiads among the Diclinous Garryal Alliance, not to name 

 many other similar cases. So that the Epigynous Sub-Class may be 

 likened to a great kingdom lying in the midst of many others, just as 

 Germany is bordered by France, Holland, Denmark, Poland, Hungary, 

 Turkey, Italy, and Switzerland. 



In the two previous Sub-Classes the Epigynous character occasionally 

 breaks out, and sometimes in a very unexpected way ; as when the genus 

 Eupomatia appears in the hypogynous Ranal AUiance ; and in many of 

 the Saxifragals. In like manner, both Myrtleblooms and Melastomads have 

 species in which the calyx has but little union with the ovary ; these are, 

 however, beyond all question, exceptional instances. 



It is here assumed that the inferior ovary is always formed by an adhesion 

 of the calyx to its sides. There may, however, in some cases, be justice in 

 the assertion of Schleiden, that the real inferior ovary is caused by a 

 hollowing out of the peduncle, analogous to what takes place in the common 

 Fig. {Ann. Sc. 2 ser. XII. 374.) Possibly such is its origin in Loranths, 

 Cucurbits, Sandalworts, and others in which no calyx-veins are to be found 

 on the surface of the fruit ; and Eschscholtzia may be considered to ofi'er an 

 obvious explanation of this, its peduncle forming, round the base of the 

 ovary, a cup which evidently has nothing to do with the calyx. If that is 

 so, then the structure of Calycanths, the Rose, and many more will bear a 

 similar interpretation. But it is impossible to admit that such is the origin 

 of all the ovaries with a superior calyx. Melastomads, for instance, have 

 evidently a true calyx tube ; and even in Umbellifers the presence of an 

 adherent calyx tube is demonstrated by those monsters of the wild Carrot 

 which are sometimes found in fields with their 2 carpels in the condition 

 of ordinary leaves ; in such instances these carpellary leaves spring from 

 the central axis, and are surrounded by the tubular but non-adherent calyx. 



Whatever may be the true theory of the inferior ovary, it seems to be a 

 very important point of structure, collecting together species having more 

 resemblance to one another than to anything else, and therefore of great 

 value for natural classification. 



