REPORT ON THE MONAXONIDA. 67 



Esperella magellanica, Eidley, sp. 



1881. Esperia magellanica, Ridley, Proc. ZooL Soc. Lond., January 1881, p. 117, pi. x. 



fig. 5, a. b. c. d. e. 



1882. Esperia Cunninghami, Carter, Ann. and Mag. Nat. Hist., ser. 5, vol. ix., p. 300, pi. xi. 



fig. 17. 



This species has already been described by Eidley {loc. cit.), we shall therefore 

 only add a few particulars to that descrijation. The pores, which have not been 

 hitherto described, are very distinctly shown in the Challenger specimen. They are 

 round openings in the dermal membrane, about 0"1 mm. in diameter, which occur 

 irregularly scattered between the reticulations of the dermal skeleton ; they do not seem 

 to be localised in pore-areas. 



Immediately beneath the dermal membrane occur immense quantities of large globular 

 yellow cells, measuring 0'02 mm. in diameter, usually aggregated in heaps so as to 

 rfesemble the roe of a herring. When mounted in Canada balsam without staining, these 

 bodies appear of a deep yellow colour. They stain fairly readily with borax carmine ; 

 when treated with a strong solution of iodine in hydriodic acid they assume a purple 

 tinge, and then become black. Sometime a distinct, large nucleus can be distinguished, 

 but more often the cells seem simply to be filled with a granular substance. We think 

 there can be little doubt that these bodies are parasitic Algse, and not, as stated in Eidley 's 

 original description, pigment-cells. 



This species was originally discovered by the " Nassau " expedition, and is mentioned 

 in Dr. Cunningham's Notes on the Natural History of the Strait of Magellan, 1871, 

 p. 481. 



Zoca%.— Station 313, January 20, 1876; lat. 52° 20' S., long. 67° 39' W. ; 

 east of Cape Virgins, near the entrance to the Strait of Magellan ; depth, 5 5 fathoms ; 

 bottom, sand; bottom temperature, 47° '8. One good-sized fragment. 



Habitat. — Sandy Point, Strait of Magellan (Eidley, " Alert ") ; Otter Island, 

 Patagonia (Cunningham) ; east of Cape Virgins (Challenger). 



Esperella murrayi, Eidley and Dendy (PI. XIII. figs. 11, 13, 14, 16, 17, 18; 

 PI. XIV. figs. 1, la). 



1886. Esperella murrayi, Ridley and Dendy, Ann. and Mag. Nat. Hist., ser. 5, vol. xviii. p. 338. 



Sponge (PI. XIV. fig. 1) massive ; lobate. Arising from a comparatively narrow 

 base (41 mm. in greatest diameter), it rapidly expands, and is broadest near the 

 summit, having a maximum breadth of 116 mm. Height, 162 mm. The shape may 

 be roughly compared to that of an inverted triangular pyramid. A broad, rounded 

 lobe occupies each corner of the base of the pyramid ; and between these lobes, 

 instead of a flat base there is a deep depression, while dow'n each of the remaining 



