470 MR. E, A. NEWELL ARBER ON THE 
bracteolar sheath, are Z. Aucheri, Jaub. & Spach*, L. gyno- 
chlamydea, Hemsl.t, L. hypoleuca, Deene., L. quinquelocularis, 
Hardw., and L. Ferdinandi, Franch. t 
The function of the bracteolar sheath is, no doubt, to afford 
protection to the young fruits. In all the above-mentioned 
species the fruits as they mature either grow out of the 
sheath, usually splitting it laterally (L. iberica), or where the 
bracteoles are free laterally the sheath becomes reflexed 
(L. involucrata). 
In at least two other species, Z. ligustrina, Wall., and L. 
pileata, Oliver, additional protective coverings to the ovaries and 
young fruits are found. The flowers of L. ligustrina, Wall., an 
East-Indian species which Koehne§ has figured, possess in 
addition to the bracteolar sheath a further and still outer in- 
tegument, which is developed from the region of the calyx-tube, 
and which grows downwards, overlapping the bracteolar sheath. 
When the fruits are ripe they project beyond the bracteolar 
sheath, as in LZ. iberica, and bear at the apices the withered 
remains of the upper integument. The two fruits, as also the 
two ovaries, are quite free from one another and from the brac- 
teolar and upper sheaths. In Z. pileata the upper and outer 
envelope is also present ||, and probably also in Z. vesicaria, 
Komar {._ I have not, however, seen this latter species. 
Type of Z. cerulea, L. 
In tho-e species which possess a more or less well-developed 
bracteolar sheath, we have seen that the two ovaries and the two 
fruits are entirely free from one another. We have also traced 
the fate of the bracteolar sheath when the fruits mature. We 
are now in a position to understand the origin of the false 
synanthy in the isolated type, L. ce@rulea, L., a common 
European alpine, and a species of great morphological interest. 
A completely fused bracteolar sheath is present in this species 
surrounding the two ovaries (fig. 2). The ovaries are, as in 
L. iberica, quite free from one another, although externally they 
appear to be completely fused. 
* Jaubert & Spach (1842), tab. 73, p. 187. 
+ Forbes & Hemsley (1888), p. 362. 
{ Also? L. minuta, Batal., vide Batalin (1892), p. 170. 
§ Koehne (1891), p. 167, fig. 57 7. 
| Figured by Oliver (1887), pl. 1589. 
“| Komarov (1901), p. 427. 
