76 Proceedings of the Royal Physical Society. 



Wyville Thomson lias kindly permitted me to exhibit a 

 specimen in this condition. 



In 1868 Drs Herklots and Marshall described* a new 

 form, to which they gave the name of Euplectella Owenii. 

 Five examples of this species were brought from Japan by 

 Major von Siebold, and these are now in the Leyden Museum. 

 Unfortunately no indication of the depth from which these 

 were obtained is given. Moj^leciella Oivenii is oval instead 

 of round in transverse section, and wants the apical frill. 

 This species and a number of other hexactinellids are de- 

 scribed at length by Dr William Marshall in his admirable "Un- 

 tersuchungen iiber Hexactinelliden." f This author regards 

 E'lL'plectella aspergillum and cucumer (Owen) as being specifi- 

 cally identical — an opinion now very generally accepted. It is 

 worthy of notice in this connection, that Dr Marshall con- 

 templates the possibility of the existence of ramose or colonial 

 forms of Euplectella, as he writes, J '* Es wiirde mich wenig 

 wundern, wenn z. B. Formen gefunden wiirden, die nicht 

 mehr aus einer Person bestanden sondern einen Cormus 

 bildeten." The contour of the abnormal specimen now 

 exhibited seems to favour this hypothesis. 



Sir Wyville Thomson has recently described § and figured a 

 third species, Euplectella suberea, obtained during the voyage 

 of the " Challenger," at a depth of 1090 fathoms, ninety miles 

 south-east of Cape St Vincent. This is the only Atlantic 

 form of the genus at present known; but Sir Wyville 

 believes in the existence of others from fragments obtained 

 during dredging, too imperfect indeed for description, 

 but evidently belonging to distinct species. Euplectella 

 aspergillum was obtained in the living state in considerable 

 numbers by the naturalists of the '* Challenger " off the 

 island of Zebu, one of the Philippines, at depths of 95 to 100 

 fathoms. All the "Challenger" specimens possess the 

 normal form. 



Captain Chimmo, E.N., has recently published an interest- 



* Archives neeiiandaises, Bd. iii. 



-t- Zeitschrift fiir Wiss. Zool., xx. Bd. Suppl.-Heft. 



X Loc. ciL, p. 209. 



§ "Voyage of the ' Challenger '—The Atlantic," voL i., p. 133. 



