te 



REPORT ON THE CALCAREA. 27 



G. Anamixilla,* n. gon. 



Syconidse without any special tubar skeleton, the supporting spicules of tl 

 parenchyma disposed in it like those in the Leuconidae ; in most cases, however, more or 

 less parallel to the outer surface. 



A certain analogy exists between Anamixilla and Ileteropcgma, and this analogy 

 (•(insists in the possession of a kind of spiculation which docs not influence the form of 

 the radial tubes. The tubar spicules of Heteropegma are too minute for it ; the tubes of 

 Anamixilla have no special skeleton at all, the spicules of their parenchyma showing an 

 irregular " leuconoid " disposition. And, accordingly, the form of the radial tubes in both 

 the cases is inconstant, they are of irregular outlines, may take an oblique course, and 

 show an inclination to ramify. 



The genus Anamixilla is hitherto represented by a single species : — 



Anamixilla torresi, n. sp. 



This species must undoubtedly be regarded as the representative of a new genus, for its 

 organisation contains a new principle, and it is more than probable that there will be 

 found Calcarea adhering to this principle, but presenting different variations in regard to 

 the form and quality of their spicules. 



I let the genus Anamixilla follow the genus Amphoriscus ; a close relationship 

 between these two genera cannot certainly be proved, but may be considered as very 

 plausible, owing to the presence in my Anamixilla torresi of the peculiar subgastric trira- 

 diate spicules, so characteristic and of so great importance for most forms of the genus 

 Amphoriscus. In Anamixilla torresi these subgastric sagittal spicules, compared with 

 the large triradiate spicules of the parenchyma, are evidently too small and slender to 

 be of any important physiological significance, and therefore can be regarded, not without 

 reason, as an index of the phylogenetic affinities of the genus. 



In the Family Lcuconidse I distinguish the following genera : — 



Leucilla, Hseckel 8 (sensu mutato). 



Leuconidae with flagellated chambers of an elongated, cylindrical form, recalling that 

 of the radial tubes of the Syconidse, with the skeleton of the parenchyma bearing some 

 traces of a certain regularity in the arrangement of its constituent parts, owing to the 

 disposition of the subgastric and subdermal spicules opposite to each other. 



1 Kiilksclnvanmie, Bd. ii. p. 2">!>. '- From dvaftiz, confusedly, pell-mell 



3 Kalk.-chwainnic, Bd. ii. p. 132. 



