96 



that the sides of the stalk seem to form shallow grooves. It has a yellow colour. 

 At the lower end there is a distinct enlargement with very prominent angles, and 

 from this point the stalk tajiers until a short distance below the rachis, where it 

 again forms a distinct enlargement which gradually increases in size till it joins 

 the lower end of the rachis. 



The axis is quadrangular in section, with the sides so deeply grooved that the 

 whole appears like four united pillars. At its lower end the axis is 2 mm. in 

 diameter ; it gradually tapers to the tip, which is hidden in the rachis. 



The rachis is short, and has the appearance of a swollen part of the stalk. It 

 carries a large number of autozooids, which all reach the same height or nearly 

 so, the lower ones being the longest. The rachis is bilateral, although the 

 crowded state of the autozooids almost entirely hides this arrangement. One 

 specimen from which they were cut oft' showed that they stood in four irregular 

 circles or whorls, the outermost containing 7, the next 12, the third 14, the fourth 

 10, and in addition there were 7 autozooids at the very tip that had no definite 

 arrangement. The autozooids are very long, 42 mm. in maximum length, with a 

 diameter of 3 mm. The tentacles are long and tapering, with one row of bluntly 

 conical pinnules on each side. In the basal portion of the autozooids there is an 

 abundant supply of ova about 0'75 mm. in diameter. The autozooi<ls are 

 yellowish-white to transparent in the lower parts, and greenish-black in the upper 

 part ; the aboral surface of the tentacles has a bluish tinge, and the oral surface 

 and pinnules is light brown. 



Siphonozooids are numerous on the basal part of the rachis ; they are prolonged 

 into A-shaped points on the pararachidial and metarachidial surfaces, and they 

 completely cover the j^rorachidial surface. 



Spicules are absent throughout the specimen. 



Locality : Andamans. 



Umbellula elongata, n. sp. Plate VII. fig. 6. 



This species is represented l)y one complete colony, about 631 mm. in length. 



The axis is more or less quadrangular in the lower part, and looks as if it 

 were formed from four pillars fused where they touch. It becomes circular or 

 oval in section in the upjjer part. It has a diameter of 2 mm. near the base. 



At the lower end of the stalk there is a large swelling, which reaches its 

 maximum diameter, 10 mm., at a jJoiut 86 nun. from the base. From this point 

 upwards the stalk, which is thickly covered by siphouozooids, gradually tapers till 

 it reaches the Ijeginning of the rachis. On the lower part the coenenchyma is 

 thick, but on the upper part it is thin, except at the two opposite sides, where it 

 forms a continuous fold which runs the whole length of the axis. 



The rachis is long, gradually thickening from its junction with the stalk and 



