STUDIES ON THE COMPAEATIVE ANATOMY OF SPONGES. 243 



we now also know a species, H. latitubulata (4), very closely 

 resembling the first^ from Victorian waters. 



Genus 17. — Amphoriscus (Haeckel [20], emend.). 



Diagnosis. — The flagellated chambers are elongated, and 

 arranged radially around the central gastral cavity. There is 

 no articulate tubar skeleton, but, in addition to the subdermal 

 quadriradiates, subgastral sagittal triradiates or subgastral 

 quadriradiates may also be present. 



Remarks. — In his ''Prodromus^^ (20) Haeckel proposed the 

 generic name Amphoriscus for a very natural group of three 

 species, all characterised by the Syconoid type of canal 

 system and the presence of quadriradiate spicules only in the 

 skeleton. Of the highly characteristic arrangement of the 

 skeleton, with subdermal and subgastral quadriradiates whose 

 apical rays point in opposite directions, his generic diagnosis 

 takes no notice. This arrangement, however, is exhibited by 

 all the species referred by Haeckel to the genus, and affords, 

 to my mind, a much more suitable foundation for a generic 

 diagnosis. In his monograph (5) Haeckel altered the generic 

 name to Sycilla, but retained the old diagnosis {" Sycones 

 spiculis quadricruribus^'). He also added a fourth species 

 to the genus. 



Polejaeff (8) retains the genus Amphoriscus, but extends 

 the diagnosis to include species with subdermal sagittal tri- 

 radiates, which, in my opinion, must be kept quite separate 

 in the genus Grantessa. His Amphoriscus poculum and 

 A. flamma both belong to the genus Grantessa. His 

 A. elongatus, however, must be retained in the genus 

 Amphoriscus, and is, indeed, a very noteworthy species; 

 for, although the articulate tubar skeleton has been lost, the 

 subgastral sagittal triradiates still persist, and have not yet 

 been replaced by subgastral quadriradiates, as in all HaeckeFs 

 species of the genus. Von Lendenfeld (10; follows Polejaeff 

 in including in the genus Amphoriscus species with sub- 

 dermal sagittal triradiates as well as those with subdermal 

 quadriradiates, while he separates, quite unnecessarily to my 



