212 On some Irish Sponges. 



Notfs on some of the Species. 



Hamacaiitha johnsoni (Bawerbaiik) and fl. fulcula 

 (Bowerbank). 



A great deal of confusion exists witli regard to these two 

 species. An exaniinaLion of the type-slides showed that 

 Hamacantha johnnoni possesses tiie following kinds of 

 s|)icules — oxea, diancistia of two forms, and signiata, — while 

 Hamacantha falcuta possesses styli, diancistra of three forms, 

 and toxa. The toiiner species, in fact, has in recent years 

 been called llumacaatha schinidti (Carter) and the latter has 

 usually been ref-n-red to as Hamacantha johnsoni (Bower- 

 bank)'. 



Rhaphidotheca mar shall -halli, Kent. 



Two specimens of Rhaphidotheca are in the collection — one 

 with exotyles of the shape characteristic of R. marshall- 

 halli, Kent, and the other with exotyles shaped like those of 

 R. ajffinis^ Carter. From an examination of the two speci- 

 mens it has been decided to regard the latter name as a 

 synonym of R. marshall-halli. Tiie union of these two 

 species has been suggested trom time to time by various 

 authors. 



(?) Clathria anchorata (Carter). 



Tiiis sponge, which is doubtfully referred to the genus 

 Clathria, was described by Carter under the name Dictyo- 

 ci/lindrus anchorata. 



Anchinoe Jictitius (Bowerbank) . 



The sponge called by Bowerbank Microciona fictitia was 

 found to have the same arrangement of the skeleton and the 

 same kinds of spicules as Hymeniacidon perarmatus, Bower- 

 bank, wliich is tiie type-species of Gray^s genus Anchitioe. 

 This genus may be detined as follows : — Ectyonina3 with a 

 skeleton composed of brauchiiig fibres which consist of 

 multiserially arranged smooth diactinals echinated by 

 acaiithostyli. No special dermal skeleton. Microscleres 

 isochelai arcuatai solely, or perhaps with other forms. 



Plumohalickondriaj Carter, must be regarded as a synonym 

 of Anchinoe, Gray. 



