Ixxii 



INTRODUCTION. 



Fig. xxxiii. 



Avicularium of Scrupocellaria scruposa. 



w. Wall of zooecium. c. Chamber of avicularium. m. Muscles. 

 p. Peduncular portion, b. Beak. md. Mandible. 



mobility is perhaps the most essential distinction between 



this form and the avicularium of Bugula ; the beak and 



mandible are less highly organized 



than in the latter ; but the general F 'g- i^ 



character is the same in both, and 



very slight changes would suffice to 



convert the one into the other. 



In Scrupocellaria the avicularium 

 is attached to the side of the zocecium 

 by its entire length ; but it is truly 

 pedunculate (Woodcut, fig. xxxiii.), and 

 if attached only by the base, would 

 bear a close general resemblance to 

 the Bugulan form. The mandible 

 is curved in towards the extremity, 

 and the beak is somewhat hooked ; so 

 that the appendage has considerable 

 prehensile power. The chamber is 



not more than sufficient for the lodg- Pedunculate avicularium 



ment of the muscular fascicles. Bicellaria tuba. 



