1886.] Or. King — Kew Species of Ficus fi'om New Guinea. 397 



distended appearance of tough membranous wall (false pericarp). The 

 style is, as a rule, much shorter and straighter than the style of the 

 . fertile female flower, and more terminal ; and it has very frequently a 

 dilated tubul?4,r apex which occupies the situation of the true stigma, but 

 has often little or none of the viscid parenchyma characteristic of that 

 organ. These peculiarities in the nature of the stigma and the shortness 

 of the style are apparent in the gall flowers of many species from a very 

 early stage. They are not consequences of the deposit of the egg of 

 an insect in the ovary, but, as Count Solras-Laubach points out {Bot. 

 Zeitung, I.e.), such original peculiarities in the style and stigma of 

 the gall flower may rather determine the selection of it by the insect 

 as the nidus for its egg ; for in many of the species of Blastophaga and 

 of some other Hymenopterous genera which visit figs, the ovi-positora 

 are not long enough to reach down the longer and more curved styles 

 of the perfect female flowers. There are, however, many species of 

 Ficus (more especially in the group Urostigma) in which the gall and 

 fertile female flowers are not characterised by any marked differences 

 in the form of style and stigma, and it is only by cutting the ovaries 

 open that the two can be distinguished. 



" Now there is probably nothing in itself very remarkable in the 

 mere occurrence in the genus of numerous flowers having the general 

 form of females, which yet, by reason of certain peculiarities in their 

 structure, are incapable of fertilisation by pollen and are practically 

 barren, while at the same time their very structural defects fit them for 

 becoming the nidus for the eggs of special insects. But when the 

 manner in which these malformed female flowers are disposed in the 

 receptacles is inquired into, it becomes clear that, through the interposi- 

 tion of insects, these malformed females play a most important part in 

 the life-history of many species of the genus. In all the species, except 

 those included in the section Urostigma, the gall flowers occupy the 

 same receptacles as the males, while the fertile female flowers occupy 

 different receptacles. In other words, the majority of the species have 

 two distinct sets of receptacles — one set containing male and gall flowers, 

 but no fertile female flowers, and another set containing only fertile 

 female flowers without any trace of either male or gall flowers. The 

 proportion of males to gall flowers in receptacles of the former kind 

 varies. In all (excepting ;^he JJrostigmas just mentioned) it is the rule 

 to find the males confined to a zone of greater or less width at the apex 

 of the receptacle just under the scales which close its mouth. Some- 

 times this zone is very narrow indeed, and consists of only a single row 

 of male flowers, and that row not always a complete one ; the remain- 

 ing part of the interior of the receptacle being occupied by gall flowers. 



