Ixxxviii PROCEEDINGS OF THE ROYAL HORTICULTURAL SOCIETY. 



and had likewise become stupefied, and had fallen to the ground, but, 

 gradually recovering, ultimately quite revived. Mr. Massee, V.M.H., said 

 he had frequently noticed the same thing at Kew, and had also seen the 

 wasps eat their way out of the tube after being imprisoned, but had never 

 observed bees doing this. 



u^cidmm on Abies. — Mr. Saunders showed leaves of Abies Pinsapo 

 having numerous fecidia of the fungus formerly known as ^cidium 

 pseudo-cohimnare, the white pseudo-peridia of which occur in two rows 

 on the under surface of the affected leaves, which are somewhat paler 

 than the healthy ones, and stand like little cups one -eighth of an inch 

 in height. The teleutospore stage is known as Melavipsora GcBppertiana. 



Bulbils on Horseradish. — Rev. Professor Henslow showed an 

 inflorescence of horseradish with abortive flowers, and upon which were 

 numerous bulbils replacing the flowers. 



Cleistogamous Floicers. — He also showed runners of Viola which had 

 during the summer produced cleistogamous flowers only, but which were 

 now bearing normal flowers, thus bearing out the observation he had 

 before made that the production of cleistogamous flowers was largely 

 due to climatal conditions. — Origin, "Floral Structures," p. 262. 



" Grit " in Apples and Pears. — Adverting to this subject, which 

 formed the text of a communication at the last meeting. Professor Henslow 

 said : — " The theoretical origin of grit I would attribute to the breaking 

 down of the ' stone ' of such a fruit as that of Cratcsgus. In the 

 formation of an ' inferior ' ovary by the fusion with the ovary of a 

 receptacular tube (calyx tube), the interior epidermis of the tube (as in 

 Prunus) and the exterior one of the ovary are totally arrested ; so that 

 the central parenchymatous tissues of both are fused into one common 

 layer, the * pseudocarp.' In forming the fruit of the pear or apple there 

 is no true epidermis inside the ovary cells ; but the core consists of tiuo 

 fibrous layers confluent with the external parenchyma. If there be a 

 stone, as in haws, this is usually described (as is also a cartilaginous core) 

 as the endocarp. As, however, there is now no true mesocarp, and the 

 stone is only lined with a thin fibrous layer, I would regard this latter 

 as the homologue of the core of a pear from which the stone is gone. 

 As this is produced by the formative tissue of the pseudocarp (which is 

 continuous from the core to the epidermis), it might be either carpellary 

 or axial ; as ' grit ' it may be found anywhere. 



" Another suggestion in support of the theory arises from affinities. 

 The tribe Pomece has nine genera ; five have stone fruits, three have 

 berries ; one, Pyrtis, has ' a cartilaginous, very rarely a crustaceous or 

 bony endocarp' (Bentham and Hooker). Hence the stone-fruit genera 

 form the majority and probably the ancestral condition ; but the stone, 

 or sclerenchymatous cellular tissue, being more or less arrested, has given 

 rise to the baccate instead of a drupaceous fruit, and to a cartilaginous 

 core. If we turn to the tribe Poteriece, of the ten genera included in it 

 at least four have an * indurated ' receptacular tube ; while that of 

 Margyricarpus is described as * coriaceous or nucumentaceous ' ; and of 

 Bencomia it is said ' the achenes are " closely invested " (arete concreta) 

 by the globose calyx tube into a drupe with a somewhat bony stone 

 (putamine subosseo).' If, now, the tube of the plum should ever become 



