121 
ated oval shape (Plate III, Fig. 18), its more moderate thickness, 
and its nicely extended condition when preserved; that is, it is 
not rolied or folded. The same condition is met with in Cr. wahl- 
bergi Bock. The absence of well-developed tentacles definitively 
shows that it does not belong to the genus Stylochus. 
The upper side of the body has (in the preserved State) a very 
even, homogeneous, dark grey-brown colour without concentration 
of the shade toward the median line. The colour belongs to the 
epidermis and is dependent upon the presence of the glandular 
secretion, which in the formalin-preserved animal shows such a 
tint. The outer margin of the body and the very low tentacular 
protuberances are colourless. The marginal eye-band was already 
easily discernible on the specimen in formalin by means of a 
lens. The under side of the body is lighter brown, as the amount 
of epidermal giand cells is somewhat sparser. 
The tentacles are present only in the shape of extremely small 
knobs, and can be perceived as insignificant prominences by means 
of a strong lens or in the microscope. On account of their 
glandless epithelium, they are visible on Plate III, Fig. 18 as two 
light spots. 
Measurements: The length of the body is 40 mm., and 
its greatest width 20 V 2 mm. The tentacular rudiments are 8 mm. 
from the frontal end and 1,6 mm. apart. The mouth is 28 mm. 
from the anterior end. Pharynx begins 10 mm. from the frontal 
end of the body and is nearly 24 mm. long. Thus the post-phar- 
yngeal section is only 6Vs mm. The female gonopore is 4 mm. 
from the caudal end of the body and SVs mm. back of the male 
opening. The latter is, moreover, 1 mm. in front of the caudal end 
of the pharyngeal pocket. 
Arrangement of eyes: Text-figure 14 shows the arrange¬ 
ment of cerebral and tentacular eyes. It should particularly be 
emphasized that the marginal eyes are unusually numerous and are 
found around the entire body, being also frequent at the caudal 
end (text-fig. 15). Many eyes are present over the entire anterior 
end of the animal, and posteriorly they extend to the pharyngeal 
pocket. Frontal eyes are arranged in scattered groups or detached 
and are most frequent in the median part. The tentacular eye- 
groups (text-fig. 14, tento) are well marked off and each consists 
