﻿^04 "ENDEAVOrE" SCIENTIFIC RESULTS. 



(a) According to Lendenfeld : — 



P. ch'i^cuis. A reticulate mass of regularly cylindrical 

 branches on an average 5 mm. thick ; spicules, 

 smooth styli 160 x 6 ;* and 70 x 5 //, the latter echin- 

 ating. (Loc, Port Jackson.) 



P. arborea. Dendritically ramifying, with clearly- 

 defined stem. The styli measure 80 x 4 ji and 50 

 X 4 K respectively. (Loc, Port Jackson.) 



P. niacroponi. Small and tender, reticulate, honey- 

 comb-like, incrusting or massive ; smooth styli 200 

 X 4 ;< ; echinating spined styli 70 x 6 ju (Loc, 

 I'orres Strait.) 



(h) .\ccording to Whitelegge : — 



P. cJegans. With erect, rarely coalescent branches, 

 generally with distinct peduncle; spicules, styli 100 

 X 6 ji and 80 x 5 ^ respectively. (Loc, Port Jackson 

 and neighbourhood.) 



P. arborea. A (laihria; reticulately branched in one 

 plane ; spicules, styli 180 x 8 ji, subtylostyli 200 x 2 /i, 

 acanthostyles 85 x 6 ji. (Loc, Port Jackson and 

 neighbourhood.) 



P. macropora. Forming low densely-branched clumps, 

 with abundant anastomoses of branches. Spicules, 

 smooth styli 100 x 4 /i and 75 x 4 }i respectively, 

 (Loc, neighbourhood of Port Jackson, common.) 



A comparison of the descriptions of P. arborea, Lendf. , 

 .and P. elegans, Whitelegge, points almost incontestably to 

 the conclusion that they are one and the same. Clathria 

 {Plectispa) arborea, Whitelegge, is therefore quite a different 

 sponge from Lendenfeld's species and requires a new specific 

 name, for which I propose multipes. Echinoclathria {Plec- 

 tispa) macropora, Whitelegge, is, as mentioned, a common 

 local sponge, and must have been familiar to Lendenfeld. It 

 evidently affords no grounds for its identification with P. 

 macropora, Lendf., which, moreover, is recorded from a 

 widely distant locality. Neither does it show sufficient agree- 

 ment with P. elegans to warrant its identification to that 

 species. There is no other course open but to regard it as a 

 new species ; it is described in the present paper under the 

 name of Echinoclathria ramosa. P. arborea, Lendf., is like- 

 wise a species of Echinoclathria, and there can be little doubt 

 that P. elegans, Lendf., belongs to the same genus. The 

 ^enus Plectispa is accordingly left with a single species, P. 

 macropora, which may therefore be considered as the type. 



