No. 407.] DOUBLE LOXOSOM.E. 893 
eighteen and twenty tentacles. In the parts located in the 
body, abnormalities occur in digestive, reproductive, and ner- 
vous systems. The position and arrangement of the buds is 
also peculiar. 
The digestive 
tract consists of 
a single bilobed 
stomach, into 
which lead two 
gullets, and from 
which lead two 
intestines, one 
gullet and one 
intestine having 
the normal rela- 
tion to each 
lophophore. 
The sexual 
organs consist 
of three testes, 
one median 
above the stom- — 
ach somewhat Fic. 5. — Anterior aspect. 20 and 18 tentacles. +. = rectum; 
s. =: stomach; 7. = testis. x 57. 
larger than the 
others, and one on the outer side of each cesophagus. A pair 
of seminal vesicles, one on either side of the median testis, 
open to the exterior in normal positions with respect to the 
two lophophores. From each of the lateral testes a duct com- 
municates with the adjacent vesicle. The median testis has an 
opening into the left-hand seminal vesicle, but I have been 
unable to detect one to 
that on the right side, 
though the two organs 
lie close together, their 
Fic. 6. — Outline of brain made by superposing successive cavities separated only 
pe pe o by a membrane. 
The brain has the form shown in Fig. 6, the median portion 
being somewhat higher than the ends and directly above the 
