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It is expaiuled in one plane and consists of a main stem which bifurcates at a 

 distance of 40 mm. from the broken end. One of these two main branches 

 again divides dichotomously after a distance of 40 mm., but the other extends 

 to the top of the colony. On the latter the simple branches, seven in number, 

 seem to arise all from one side, but this appearance is in reality due to a twist- 

 ing of the axis. On one of the tertiary branches two twigs arise together near 

 the tip and are l)ound for a short distance by the fusion of the coenenchyma, 

 but they eventually diverge. 



The branches are slightly flattened in the plane of ramification. They 

 vary very little in diameter but are slightly conical at the tip. 



The coenenchyma is fairly thick and is marked by a deep longitudinal 

 groove which extends on each of the two surfaces in the plane of ramification. 

 These are due to the collapse of the large nutrient canals. They are very 

 sinuous and sometimes appear to ascend in a spiral, owing to a twisting of the 

 axis. In some places this feature is so marked and the depressions are so deep 

 that a cross section of a branch appears like two circles overlapping on a short 

 common chord. 



The polyps are disposed in two irregular rows on each side of the stem and 

 branches. They are completely retractile within the ca'nenchyma and appear 

 as elongated depressions or slits, showing an octo-radiate figure which is visible 

 even to the naked eye. 



The axis is extremely calcareous and is of a pale yellow colour ; it is 

 cylindrical and presents a rough appearance on the surface. 



The spicules are spindles with generally four to six whorls of rough warts. 

 The whorls are about equidistant, but sometimes the two middle whorls are 

 separated by a greater distance than the others, so that the spicules approach 

 the type known as " double-spindles ". They have the following measurements, 

 length by breadth in millimetres : — 



013 X 005; 012x005; Oil x 0-04; O'OS x O'OS ; 007 x 004 ; 0065 x 0035 ; 

 0-05 x 0-03 ; 0-045 x 0025 ; 004 x 003. 



Locality : Andamans. 



Previously recorded from Prince Edward Island, 310 fathoms (" Chal 

 longer ") ; Cheval Paar, Gulf of Manaar (Herdman's Collection). 



Family Gorgonellid^. 



Nicella reticulata, n. sp. 

 ,, pustulosa, n. sp. 

 Juncella racemosa, Wright and Studer. 

 Verrucella flexuosa, Klunzinger. 

 Gorgonella umbella, Esper. 



,, granulata, Esper. 



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