308 ]>LATE LXXXA'III. 



found in considerable numbers at one locality at the 

 mouth of tlie Mersey, and tliat the largest he has seen 

 was eight inches in height with a lateral spread of 

 about six inches ; and among other specimens sent 

 to nie from the Liverpool Museum for examination 

 there was a specimen of I. varians of a rudely 2:)almate 

 form rather less than two inches in height and 

 rather exceeding half an inch in breadth. No two of 

 the larger specimens that were sent to me were alike 

 in form, and one of them eight inches in height had 

 no a,ppearance of the compact clustered form exhibited 

 by the figured one, but consisted of numerous slender 

 ascending branches dividing dichotomously at intervals, 

 and the greatest lateral spread did not exceed two 

 inches. Tliis species appears to be quite as variable in 

 the mode of the disposition of its branches, as ChaJina 

 ocnhita, which it closely resembles, but whatever their 

 height and size may be, they alwa3fs appear to be vei'y 

 mucli more slender and delicate than those of ('. 

 or II lata, for Avhich they might otherwise be very readily 

 mistaken if jtulged only by their external characters, 

 and this error is flic more like!}' to occur as the 

 disposition of flic oscula in both species is alike. In 

 structural characters, Avhafever may be the size of the 

 specimens, they all agree mth those of the little type 

 one in the British Museum. 



In the description of the specific characters of the 

 type-specimen, page 281, vol. ii, I have stated "surface 

 smooth and even." In these better preserved speci- 

 mens the surface is minutely hispid by the prolonga- 

 tion of the j)rimary hues of the skeleton. 



The increased knowledge that we have obtained of 

 the structural peculiarities of this sponge renders it 

 necessary that we should reconstruct its specific cha- 

 racters, and I propose that the foUowhig should be snli- 

 stituted for those in \o\. ii, page 281, 'Men. Brit. 

 Sjiongiada^.' 



