STRUCTURE AND DEVELOPMENT OF LOXOSOMA. 
277 
corresponds completely to the substance existing in the same 
position in an ordinary Trochosphere before the appearance 
of a definitive body cavity. 
The connective-tissue cells of Loxosoma are large and 
granular (fig. 10), usually elongated, and giving off processes 
anastomosing with those of other cells ; they occur in all parts 
of the body — in the axis of the stalk, at the sides of the 
stomach, in the tentacles, and so on. In Pedicellina (fig. 5) 
these cells are more similar to ordinary stellate connective- 
tissue- corpuscles. The muscle-fibres are elongated nucleated 
spindle-shaped cells, often branched at their ends ; they are 
best developed in the stalk, where they form a longitudinal 
layer immediately beneath the epidermis. Special muscular 
fibres are connected with the foot (in those cases where the 
foot-gland persists), the tentacles, and other parts of the body. 
I have nowhere observed with certainty the endings of nerves 
in the muscles. 
Excretory Organs. — With the details of the structure of these 
organs, so important for a correct appreciation of the syste- 
matic position of the Entoprocta, we are almost altogether 
unacquainted. Schmidt (11) has alluded to the nephridia, but 
appears to have considered them as parts of the generative 
system. Hatschek (14), who has detected them in both 
adults and larvae of Pedicellina, makes the important state- 
ment that in the former the nephridia are composed of per- 
forated cells, whilst Joliet (24), who has devoted an entire 
paper to the treatment of these organs, asserts that their walls 
are so delicate that the existence of an excretory function is 
doubtful. 
The nephridia of Loxosoma are found lying on the ventral 
wall of the stomach, one on each side of the oesophagus (see 
Joliet’s figure), and situated near the anterior surface of the 
body. In examining their structure, best observed in the 
living condition, the animal should be looked at from in front. 
The proximal portion can be investigated with more ease than 
the part which is nearer to the external aperture, since the 
organ in the latter position is covered by the oesophagus, 
