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1242 Recent Literature. [ December, 
3. The Suctorial Mechanism.—The suctorial canal begins where 
the paired limbs of the upper labellar fork are fixed on the ex- 
tremity of the upper labial plate. The entrance is guarded by 
bristles to prevent the escape of fluid. Behind this are seen the 
tips of the labrum and hypopharynx, between which the entering ' | 
fluid penetrates so as to reach the proper cesophagus. 
The labrum having radial muscles between its two plates (Fig. 
2, /m) can enlarge its lumen and so effect suction. At the triangu- 
lar “ small capsule” the action of the fulcrum comes into play, its 
muscles raising the upper floor-plate (Fig. 5, of), and so enlarg- 
ing the cavity below and continuing the suctorial process. hus 
the fluids are absorbed and forced towards the stomach. 
For dissolving solid substances the secretion of the glands is 
` provided. There are three pairs of salivary glands. The chief 
proboscis (Fig. 8, /g), large-celled round masses with a common 
duct opening near the tip of the upper labial plate. A third col- 
lection of salivary glands is at the passage of the fulcrum into the 
cesophagus. 
The salivary secretion is spread over the labellar cushions by 
means of the pseudo-trachee.! Sugar, bread-crumbs, &c., Dem 
porous absorb the fluid; it is not the sugar that is absorbed by 
the saliva, but the saliva by the sugar. 
III. Harrs Ann SENSE-ORGANS.—The proboscis is covered with 
short hairs not supplied with nerves. Besides these there are 
three kinds of special hairs : 
(1) The factile hairs are on the upper rim of the es 
cushions (Figs. 8, 9, z4), hollow, having a nerve with a gang? 
(tg) below. í 
(2) Labial glands with bristles are on the outer margin of t 
side as if for conveying a secretion outwards (Künck 
naire deem these to be sense-organs with nerve-ganglia). 
(3) There are also taste-organs over the surface of the me 
between the pseudo-trachez (Fig. 7, indicated by dots, an® © > 
10, 11). Each hair has a chitinous basal ring ; its nerve © the 
gliated, and is perforated by an axis cylinder W ine organ 
surface, indicating that here we have to do with a genuine 
of special sense. 
1 An easy experiment illustrates this. Press out the probere ga Further 
labellæ swell, their surface is covered with ‘saliva like a drop of ‘i k 
pressure swells the labellæ, and instantly the saliva disappears, bemg 
now expanded pseudo-trachez by capillary action.—G. M. 
