On the Structure and Development of the Cysticercus cellulosae, as Found in the Pig, by George Rainey

                                In concluding this Paper the Author thinks it right to 
append a brief reference to the views at present entertained 
as to the nature and relations of the Cystic Entozoa, in order 
that the bearing of his own researches may be more clearly 
apprehended. 
A similarity in the form and armature of the head in 
the Cysticercus and Tape-worm had led the earlier Ento=
zoologists to suspect that there was some latent affinity 
between the Cystic and the Cestoid Entozoa, and this 
surmise has through recent investigations grown into a 
consistent doctrine, <s>according to<\s> by which it is held that the 
Cysticercus and Taenia are but different conditions of 
the same animal. It is accordingly now believed that the 
ovum, or rather embryo, of a tape-worm, being introduced 
into the body of some higher animal, penetrates through the 
tissues, probably by aid of the three pairs of hooklets with 
which it is armed, and on arriving at a suitable resting 
place is developed into a Cysticercus - in some cases 
undergoing intermediate changes in its progress thither - 
that the Cysticercus is a creature destitute of reproductive 
organs, but that when the flesh of the animal which has 
afforded it a temporary abode is devoured by a second 
animal, the parasite, thus introduced into the ali=
mentary canal of its new host, meets with a fitting 
nidus for its further development, and, losing its 
caudal vesicle, lengthens out, acquires transverse re=
ticulation and assumes the form of a jointed tape-worm. 
The term <u>Scolex<\u> is applied to the cystic and <u>strobila<\u> 
to the taenioid form of the entozoon; and as each 
articulation of the taenia is furnished with a perfect 
sexual apparatus, and, when charged with fertile ova 
or embryos, may separate in due time from its neigh=
bours, a single segment has been looked on a consti=
tuting