238 DR. MOXON, ON MOTOR NERVE. 
and this to a very different extent on the side to which the 
nerve is attached (gg). On the opposite side to this attach- 
ment the sarcolemma fits at all times closely to the sarcous 
tissue, and it requires careful observation to see the wrinkles 
ef the membrane during contraction; but on the side to 
which the nerve is attached this membrane is then raised in 
the most obvious way into bulging folds. The inequality of 
the folding of the membrane on the two sides produces a 
puckered appearance of the oat acres, very striking during 
extreme contraction. 
What it is that occupies the space which is thus shown to 
exist between the sarcous tissue and the sarcolemma on the 
side whereto the nerve is attached I could not be certain. 
Nuclei appeared to exist at the spots where the folds became 
most prominent, and these nuclei (or this appearance of 
nuclei) are visible at the same spots in the uncontracted or 
but slightly contracted state. It should be said that these 
nuclei (gg) are very distinct from the nuclei of the sarcolemma 
(ee), both in disposition and in appearance. 
But it is not doubtful that the sarcolemma and neurilemma 
are simply continuous with each other, and that their respec- 
tive contents become continuous at the point where their 
union takes place. 
The nervous contents of the neurilemma are, then, continu- 
ous with a pellucid material disposed along the same side of 
the fibre between the sarcous substance and the sarcolemma. 
The question of the exact mode of termination of the nerve- 
cylinder after entering the muscle-fibre is hotly enough con- 
tested by Messrs. Rouget and Kiihne, and the points at issue 
have become extremely refined. In the larger fibres of verte- 
brata, on which their observations were made, the expanded end 
of the nerve-cylinder axis, which they agree to describe, may pro- 
bably be rendered necessary through the larger mass of sarcous 
tissue to be influenced by the nerve-fibre. In the instance 
I am describing the muscle-fibre is so small in proportion to 
the nerve-fibre that such an expanded nucleated plate could 
not find room, and it may be that the long, clear, uneven layer 
seen between the sarcolemma and sarcous tissue in continuity 
with the nerve may represent an equivalent structure in 
another shape. The large proportionate size of the nerve is 
worthy of remark, as it is in striking contrast with the much 
smaller relative size of the nerves of the muscles of the trunk 
in the same insects. The antenne are being constantly pro- 
truded and withdrawn, and in serving their purpose of sensory 
organs must be held under very complete and direct control 
by their muscles, It has been remarked, I think, first by 
