154 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
EXPLANATION OF PLATES. 
The drawings are by Magnus Westergren, from sketches by Alexander Agassiz. 
PLATE 1. 
Upper end of Branchiocerianthus urceolus, seen from the side (posterior) bearing 
the youngest marginal tentacles. Fresh specimen. Magnified 21. 
PLATE 2. 
Side (slightly oblique) view of same. 
PLATE 3. 
Upper end of an alcoholic specimen of same, viewed from the same side as in 
Plate 1, but as it appears when the tentacles are pinned out so as to expose the 
surface of the oral disk. 
