218 PERCY SLADEN TRUST EXPEDITION 



same work he figures practically identical pinnules for Eurete erectum, and I am strongly- 

 inclined to the opinion that they occur only as foreign bodies in Sclerothamnopsis. 

 (5) *Scopul8e, few in number and also very likely foreign. 



Neither pinnules nor scopulse occur in the specimens of Sarostegia examined by 

 Topsent and myself, but, in place thereof, the peculiar dermal spicules which Topsent 

 termed " sarules " and which I propose to call " sarulse." 



On the whole there seems to be a strong probability that Wilson's Sclerothamnopsis 

 is generically identical with Topsent's Sarostegia and Schulze's Ramella. If so, the genus 

 is a very widely distributed one, occurring in the Atlantic, the Pacific and the Indian 

 Oceans. 



Under these circumstances the question of priority naturally arises, and we have to 

 determine whether the genus is to be known as Sarostegia, Ramella or Sclerothamnopsis. 



The date of publication of Topsent's paper is May 1904, that of Wilson's July 

 1904. Schulze's report on the "Valdivia" Hexactinellids is marked " Eingegangen den 

 16 Dezember 1903," but it was not published till some time in 1904; I have been 

 unable to obtain further information as to the exact date. 



Clearly Sclerothamnopsis may be eliminated, unless it should prove necessary to 

 retain it on account of some generic peculiarity of the "Albatross" specimens, which 

 seems improbable. As between the other two names I choose Sarostegia, on the ground 

 that Schulze's genus Ramella, based upon very imperfect material, in which the 

 characteristic spicules were entirely wanting, was quite insufficiently diagnosed. 



Topsent placed Sarostegia in the family Farreidge. This family was merged by 

 Schulze [1904] in the Euretidse, in which he also included his Ramella. The reason 

 for the union of the two families was the breaking down of the distinction between 

 " Scopularia " and " Clavularia " by the discovery of the genus Olaviscopulia, described 

 by Schulze in the " Amerikanische Hexactinelliden " [1899, p. 76 &c.]. Olaviscopulia 

 intermedia, the type species of the genus, in addition to clavulse, possesses also spicules 

 of a peculiar kind intermediate between clavulee and scopulee. These spicules, which 

 Topsent terms "sarules," have the distal extremity club-shaped and beset with long 

 spines, so that the whole comes to resemble sonaewhat a besom. It is very interesting 

 to observe that sarules {or sarulse) occur also in Sarostegia, although of a somewhat 

 diflFerent form from those of Olaviscopulia. 



In his diagnosis of the family Euretidse, Schulze [1904, p. 177] says that the, 

 coherent supporting framework is composed of dictyonal hexacts, which for the most 

 part are united in a regular manner by the enclosure of the parallel apposed rays in 

 layers of silica, so as to form a scaffolding with predominantly rectangular meshes. 

 This is probably the primary arrangement of the framework in Sarostegia, but it is 

 much obscured, at any rate in the " Sealark " specimen, by the formation of secondary 

 trabeculee subdividing the primary meshes into triangular areas. 



