BY HENRY TRYON. 
41 
The Press descriptions relating to Mr. Moar’s experience 
and the facts which had now been elicited at once suggested the 
probability of the long simple tentacles of one of the Siphono- 
phora, as for example, Physalia, the well-known Portuguese 
Man-of-War, being instrumental in producing the injury 
referred to, and this view regarding its origin, was further 
supported by the characters presented by the lesion produced, 
which was in the form of a long, narrow, gradually tapering, 
tortuous and obscurely transversely barred. These tentacles are 
essentially long, vigorous, muscular, extensile tubules, which, as 
Hieckel informs us, may have a length of a yard or more when 
-contracted, but wliicli may be extended at the will of their 
possessor to a length of sometimes twenty yards. They serve 
the purpose of capturing instruments, and offensive or defensive 
weapons, and may readily get detached. And the mechanism 
to which they owe their capabilities in these respects 
reside in special organs, the possession of which has led the 
Portuguese Man-of-War to be referred to as “dangerously 
poisonous.” Viewing one side of this fishing tentacle we find it 
.almost continuously occupied and embraced by reniform bodies, 
the outer wall of each of which contains a cushion or battery, 
composed largely of urticating cells of microscopic dimensions. 
These peculiar tissue cells (cnidoblasts) have external projections 
(cnidocils), and contain specially formed capsules or sacs. These 
'Ca23sules, which bear the name of thread-cells (nematocysts), 
present the following structural characters : — The cell 2)i’oper 
consists of two membranes, and is open at one pole, where there 
is a relatively long hollow ingrowth in the form of a tube which 
has its axial portion continued in an exceedingly slender filament, 
which, being many times the length of the sac which includes 
it, is normally coiled up. The sac also contains an homogeneous 
fluid, which is said to be of a highly irritant nature. These 
nettle cells — as R. von Lendenfeld relates — are connected by a 
granular peduncle, which is really a nerve fibre, with a sub- 
jacent layer of nerve ganglia. And when the above projection 
(cnidocil) comes or is brought into contact with a foreign body, 
a stimulus is conveyed to the external network of muscular 
fibres forming the outer membrane of the urticating cell, the 
latter contracts, and by a sudden discharge the tube and slender 
