the ^Challenger ' Monaxonida. 471 



(2) dermal, cylindrical. Flesh-spicules tridentate equiancho- 

 rates and sometimes biliamates. Skeleton usually reticulate*. 



Myxilla dujitata^ n. sp. 



Digitate. Greyish yellow. Soft and spongy. Oscula small, 

 scattered. Fibre very indefinite. Spicules: — (1) entirely 

 spined acuates, size '4 by '014 millim. ; (2) bicapitate cylin- 

 dricals, with well-marked heads, size "24 by '006 millim. ; 



(3) tridentate equianchorates, with strongly curved shaft, 

 length 044 millim. 



Locality. .Station 142, south of Cape of Good Hope, 

 150 fath. 



Myxilla paucispinata^ n. sp. 



Massive, amorphous. Pale yellow. Rather soft, fragile. 

 Spicules: — (1) acuates, large, stout, usually curved, rather 

 blunt, sometimes slightly spined, size '7 by '03 millim.; (2) 

 smooth bicapitate cylindricals, with small oval heads, size '4 

 by '008 millim. ; (3) tridentate equianchorates, with stout, 

 strongly-curved shafts, length "05 millim. ; (4) slender bi- 

 hamates, simple and contort, up to '056 millim. long. 



Locality, Station 192, south of New Guinea, 129 fath. 



Myxilla mollis^ n. sp. 



Massive, amorphous. Creamy yellow. Very soft and 

 spongy. Spicules: — (1) smooth acuates or spinulates, sharp- 

 pointed, size '42 by '01 millim. ; (2) smooth bicapitate cylin- 

 dricals, with distinct oval heads, size '22 by '006 millim. j 

 (3) tridentate equianchorates, shaft slightly curved, often late- 

 rally expanded at each end, length "04 millim. ; (4) simple 

 and contort bihamates, length up to '063 millim. 



Locality. Off south-west coast of Patagonia. 



Myxilla spongiosa, n. sp. 



Massive, incrusting, extremely soft and spongy. Skeleton 

 confused. Spicules : — (1) smooth, stout acuates, gradually 

 sharp-pointed, size '7 by '02 millim. ; (2) bicapitate cylin- 

 dricals, with well-developed oval heads, usually microspined 

 at end, size '4 by '01 millim. ; (3) tridentate equianchorates, 

 with shaft laterally expanded towards each end, length '05 



* As described by Bowerbank for Halichondna. The fibre in this 

 geuus is not echinated by laterally-projecting spicules, except where so 

 stated ; the ^enus is therefore in a transitional state. 



32* 



