82 Prof. Wagner on the Stinging Organs of the Meduse. 
thread when opened up is attached, as if toa stalk; when 
stretched out, the fine thread is a line long. 
These hair or thread capsules are very loosely attached, and 
easily fall, and are rubbed off along with the slime, when the 
Medusa loses its skin ; they are found in quantity, as are also 
the threads themselves, in what is termed the stinging slime 
of the Medusz (which is nothing else than the cast-off epithe- 
lium), as is easily ascertained when these animals are kept in 
vessels. With more ditiiculty, there are locsened smaller, 
long-shaped, clear little capsules, from 53,th to ;4 5th of a line 
in size, which are partially covered with fine short little hairs, 
or whip-shaped appendages. If we compare the reserve teeth 
of crocodiles, sharks, and poisonous serpents, we cannot help 
considering these little capsules as reserve cells, when the 
larger organs are lost. 
Such individual little organs also exist beyond the spots, 
and extend to the inner rim of the arms, and to the under 
surface of the disc, where they cease. At the rim of the dise 
there hang between every two lobes (Randlappen), alternating 
with the crystalline bodies of the edge (Randkorper.2 or Crystall- 
drusen) fine long cylindrical threads of a violet colour. These 
are covered with shining hairs, and present a cylindrical epi- 
thelium, which rests on the muscular fibres ; these threads are 
covered with numerous parcels of small stinging capsules. 
It is known that the slightest touch of a Medusa causes a 
perceptible burning sensation, and I, together with several 
pupils who accompanied me in my travels, experienced it in 
bathing. This ensues more feebly or more strongly, according 
to the vigour of the animal. Meduse only sting at parts of 
their bodies where the epidermis is preserved. We never ex- 
perienced the sensation when we came in contact with por-, 
tions in which the epidermis had been removed; a circumstance 
which happens frequently in living animals. If we place a 
separated portion of a Medusa with its epidermis side on the 
bare skin, or if we rub off a little epidermis and apply it to 
the skin, a burning sensation is felt after a period of from a 
few seconds to a minute; after five minutes a slight redness 
appeared in my case, and then a simple lentil-shaped eleva- 
tion, more frequently three or four, near one another. Me-' 
