CHORDATA 433 
Lhabdopleura normani has been dredged in the Hardanger 
Fjord, off the Shetlands, and off one of the islands of the 
Tristan d’Acunha group. It consists of an irregularly branch- 
ing colony attached to foreign bodies. The zooids are very 
minute; they are connected by a stem, and the whole is 
ensheathed in a tubular investment, probably secreted by the 
proboscis (epistome). A pair of processes bearing tentacles, 
into which the cavity of the collar space is continued, exist, 
Fic. 250.—Side view of Rhabdopleura normani. Partly diagrammatic. After 
Lankester and Fowler. 
TID OU Oo DO Ht 
. Proboscis (epistome). 8. Notochord. 
. Mouth. 9. Dotted line indicating the division 
. Stomach. between the regions of the body 
. Intestine. and of the collar. 
Anus. 10. Dotted line indicating the division 
Stalk. between the regions of the collar 
. Right tentacular arm, only one row and of the proboscis, 
of tentacles is shown on each arm. 
The animal is represented as transparent to show the alimentary canal and notochord. 
and closely resemble the similar structures in Cephalodiscus. 
The zooids creep up the tube in which they are enclosed by 
means of the proboscis, and are retracted by means of muscle 
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