8 



in a good state) present in the Museum ancl to which I have given the mark B. M. 12 1 )- It 

 corresponds in every respect with Carter's description — a piece "3 inches long and 1 inch 

 square". Carter calls it "carmine-coloured" and states that the spicules are tylostyles and 

 spinispirae. We may take it therefore for granted that B.M. 12 represents a piece of Lamarck's 

 type. The fullest description of Lamarck's Alcyonium purpureum is given by Topsent, who states 

 to have examined the "holotype" from the "Jardin des Plantes", represented by tvvo "plaques 

 tres inégales". Topsent says p. 572: "Le plus bel échantillon de Spirastrella ptirpurea ne 

 représente lui-même qu'une portion d'Éponge, quelque chose comme une tranche du bord 

 progressivement aminci d'une Eponge largement évasée". The greatest thickness of this piece 

 is 24 mm. One side is not perforated and shows "de tubérosité radiales qui diminuent d'r.ipor- 

 tance du cóté marginal et s'y réduisent a de faibles bosselures". The other side has "une 

 surface egale et se perce d'orifices aquifères punctiformes visible a 1'oeil nu et tres nombreux, 



les intervalles qui les séparent étant de 1 millimètre seulement en moyenne Une écorce 



d'environ o millim. 55 d'épaisseur limite Ie corps. Elle se compose en majeure partie d'un 

 feutrage compact de tylostyles qui s'enchevêtrent clans tous les sens, mais, du cóté externe, 

 elle se termine par une croüte de spirastres épaisse de o millim. 11 a o millim. 14. Des tylostyles, 

 tous dressés verticalement, traversent cette croüte; leurs pointes dépassent d'ailleurs a peine 

 la surface générale qui, par conséquent, demeure lisse. L'interieur de 1'Èponge est ferme, 

 spongieux, non caverneux". Unfortunately Topsent does not give us any illustration of the 

 spicules. He states, however, that Carter's figures give a wrong impression of the shape of 

 the tylostyles, as well as of the spinispirae. I draw attention to the fact that Topsent correctly 

 observed that the spines of the smaller spinispirae are often not simply conical, pointed but 

 show some "épines cylindriques terminées par un bouquet d'épines secondaires minuscules". 



The name Spirastrclla pur pur ea for Lamarck's Alcyonium purpureum was first used 

 by Ridley (1. c. p. 570). Topsent confirmed the correctness of this name; at the same time 

 he mentioned the name Hardwickia ptirpurea, which is, however, a mere manuscript-name 

 (on the label of the specimen in Paris) and consequently of 110 use. 



II. Tethya bistellata — Suberites bistellatus — Hymcdesmia bistellata — Spirastrella 

 bistellata. 



1862 Schmidt p. 45—46; PI. VII, fig. 1. 



1864 Schmidt p. 36. 



1868 Schmidt p. 17. 



18S0 Czerniawsky p. 70. 



1880 Schmidt p. jj. 



1882 Carter p. 348. 



1888 Sollas p. 438 — 439. 



1892 Topsent p. 59. 



1892 (.x) Topsent pp. XVII, XXVII. 



1896 Topsent pp. 123, 125. 



1897 Dendy p. 255. 



1897 Lendenfeld pp. 55—58, 152, 156, 163, 164, 166, 168, 169, 176, 1S3, 189, 231, 232, 238, 

 239. PI. VI, fig. 59; PI. VII, fig. 65; PI. IX, fig. 120—122. 



1) A complete list of these marks is given at the end of the chapter on the synonymy of S. purpurea. 



