Dr. J. E. Gray on two new Forms of Sponges. 495 



Corpus rectum, utrinque attenuatum, sipunculiforme, bursa 

 maris triloba, Jobo intermedia prodncto, radiis septem (^quorum 

 quinque bifurcati sunt) instructo ; lobis lateraJibus radiis 

 quatuor instructis ; extremitate caudali femince oblique trun- 

 cata, subulata, apertura genitali supra caudce apicem. 



Long, feminae 10 linese, long, maris 1 uncia. 



Hab. In intestinis crassis Elephantis indici. 



Mus. Brit. 



November22, 1859.— Dr. Gray, F.R.S., V.P., in the Chair. 



Description of MacAndrewia and Myliusia, two new 

 FORMS OF Sponges. By Dr. J. E. Gray, F.R.S., V.P.Z.S. 



In 1841 INIr. Stutchbury described in our Proceedings a Sponge 

 in the ]\Iuseum at Bristol, brought from Barbadoes, which was pecu- 

 liar for being entirely formed of agglutinate silicious spicula, forming 

 a tough semitransparent glass-like spongy mass. By exchange I 

 have obtained half the specimen of this most curious and interesting 

 sponge, so that I have the means of comparing those I have described 

 with the one then made known. 



In July 1851 Mr. R. Mac Andrew kindly presented to the British 

 Museum a Coral from St. Michael's, one of the Azores, which then 

 attracted my attention, but I put it aside in hopes that I might ob- 

 tain a specimen of it in spirits, which vsould enable me to under- 

 stand more completely its history and character. No other specimen 

 having, however, come under my examination, the subject dropped 

 out of my mind. 



It was accidentally placed with the Stony Corals, and its hardness 

 and resemblance to the genus Gemmipora are some excuse for this 

 mistake. Some time ago Mr. Holdsworth, when studying the corals 

 in the Museum, observed that it evidently did not belong to that 

 group : and a very superficial inspection, indeed its mere lightness, 

 was enough to show that such was the case. 



I again placed it aside, thinking that I had seen a figure of the 

 animal as an Alcyonium in Messrs. Quoy and Gaimard's ' Voj'age,' 

 and in Dana's 'Zoophytes,' and that I would study it when I had 

 that family under my hands, or leave it for some other person to 

 examine who might take up the group. 



Having lately had occasion to consult Messrs. Quoy and Gaimard's 

 work, and the essay of Mr. Dana, I became satisfied that the sub- 

 stance from the Azores could not be the Alcyonium ylaucum or Al- 

 cyonium latum (Dana, Zooph. G23. t. 58. f. 6), which I had before 

 thought from recollection might be the case ; for these authors de- 

 scribe A. glaucum as soft and fleshy, and A. latum as " more rigid 

 in its texture than A, glaucum^ As Mr. MacAndrew's specimen is 

 hard, inflexible, and brittle, though very light, this induced me to 

 examine the specimen more carefully ; and I then found that the 

 supposed coral was a silicious sponge, covered below with a thin 

 fleshy envelope without any apparent apertures, and above mth a 

 thicker fleshy coat, studded with large-sized, regularly-disposed, cir- 



