1884.] Recent Literature. | 124I 
view that the proboscis was protruded by air-pressure was lon 
ago enunciated by Gleichen, and has been recently established by 
Macloskie and Dimmock by experiments made under water. I 
have found traces of a muscle in the head by whose action such 
inspiration may be assisted. 
imultaneously with the extension and swelling of the basi- 
proboscis, the extension of the medi-proboscis takes place. This 
is provided for by the articulation of the hypopharynx and lab- 
rum on the “ small capsule.” The long maxillary tendons (Fig. 
4, mi) are firmly united to the chitin-wall of the labrum, From 
the proximal terminal knob of these tendons a strong muscle 
proceeds to the front horn of the fulcrum (Fig. 4, me). Another 
short muscle binds the same knob to the superior wall of the 
basi-proboscis. The larger pair of these muscles are extensors of 
the medi-proboscis. 
2. Movements of the Labelle (disti-proboscis)—The bifurcating 
framework already described permits much change of the labellz. 
Muscles coming from the rigid inferior plate of the labium reach 
_ the branches of the forks, and control their movements. The 
muscles by contracting open and spread out the labellar cushions. 
_ As the muscles become relaxed the elasticity of the bars an 
_ fork-limbs suffices to bring the whole back to its position of rest. 
_ There are no antagonizing muscles to the fork-retractors. After 
_ death these retractors act so excessively as to turn the cushion- 
like labellar faces outwards. ; 
_ _As to the swelling of the labellar-cushions, Macloskie and 
Dimmock represent the tracheal air as the means of swelling. 
But careful sections shew that the tracheæ do not enter the label 
lar cushions, and there are no bladder-enlargements as must be 
Present for such an office. All the parts of the labellz not occu- 
pied by organs are filled with blood whose pale corpuscles can be 
seen. Hence it is clear that the swelling of the labellæ is caused 
by inflowing blood, as Becker supposed.” 
1T have fou lternately contracting on each side of the 
3 with scis mra pr brip M: The connection of the argik p 
tan the labrum and hypopharynx is so pliable (at least in p a y) q 
w extensor function here assigned to its ree l ‘esd 
. » Pace n “4° ished author. eer 
blood Ng “haga poa ae ae being distended mainly ym ge 
the nner 
€nt evidence to this effect be forthcoming ; an trachea j 
lp being chitinized, are not readi ecognized and ay dog ay not suffi- 
d below as glands. Kraepelin’s figures shew taat Oe ent the disti- 
icking this 
> two air-bubbles escape, and the labellar rape e f course the 
instantly collapse. Nor can they be "pe on, and easily 
Tu 
~ alt-reservoirs, when under dissection, are in the collapsed condit emen 
Piem observation; but they may be seen to swell as by peristaltic mov 
