116 TUBULARinLE. 



and twisted at the base, horn-coloured, rising to a height 

 of from 6 to 12 inches ; POLYPITES deep red ; oral tentacles 

 short and very numerous., aboral long, white, tapering, 

 about 40 in the adult ; GONOPHORES on branched pedun- 

 cles, forming large and very numerous clusters, springing 

 from the base of the lower tentacles; SPOROSACS with 

 four radiating canals and four small tubercles at their 

 terminations. 



THE habit of T. indivisa is eminently simple, though occa- 

 sionally the stems divide slightly towards the lower part. 

 At the base the tubes are much twisted and interwoven, 

 and are often agglutinated together for some distance 

 above it. 



The embryos on exclusion from the ovisac not unfre- 

 quently fix themselves on the stems, and develope them- 

 selves in this position, so as to give the appearance of 

 branching. I have seen whole colonies of young of all 

 ages grouped on the older stems. 



The gonophores are developed in great profusion, and 

 the clusters attain a large size, hanging down on all sides 

 like bunches of fruit. The sporosac exhibits in great 

 part the structure which is characteristic of the free 

 sexual zooid, but continues permanently attached. At 

 the upper extremity there is a somewhat square opening, 

 with four red spots on the margin, marking the termina- 

 tion of the radiating canals. The spadix is red and 

 conspicuous. When the embryo issues from the ovisac it 

 has twelve of the long arms, and the oral series is just 

 sprouting. 



The stem in T. indivisa is traversed by a system of lon- 

 gitudinal canals in which the circulation of the nutrient 

 fluid takes place ; these are arranged in a circle immedi- 

 ately within the outer wall of the ccenosarc, the central 

 portion being imperforate. They arc ciliated on the in- 



