922 Transactions of the Society. 



Zittel * expresses it, " Isolirto Spicula von fossilen Alcyonarien sind bis 

 jetzt noch niclit mit Sicherheit nacligewiesen worden. lliro wenige 

 Grosso cntzieLt sie nach ibrer Zerstreuung leicbt der Beobacbtung nud 

 iiberdics diirl'tc der reicblicbe Gebalt au organiscber Substanz ibre 

 Zersetzuiig bcscbleunigeu." Spicules of tbe size I bave described in 

 tbis paper migbt, bowcver, be very easily recognized, now tbat it is 

 known tbat sucb exist.f 



Evidence of tbe geological age of sucb large coenencbymal plates 

 would be of great value in aiding us to determine wbetber or no a 

 species witb large spicules appeared early in tbe bistory of tbe 

 Gorgonid Alcyonarians. At present we can only argue by way of 

 analogy frcm wbat we know about Fisbes. Tbe earliest were naked, 

 and sucb must, of course, bave been tbe case. Some of tbe latest are 

 naked too ; so nakedness j;er se offers us no aid. Tbe oldest scaled 

 forms are, like Cephalasins, formed witb great sbields. Structurally, 

 we are bound to suppose tbese great sbields were formed by tbe fusion 

 of granules ; some of tbe youngest, like Dioclon, bave large scales 

 also ; so, tbe possession of large scales is, of itself, no aid. But tbe 

 very early existence of large-scaled fisbes sbows tbat, tbougb not 

 primitive, sucb a cbaracter may bave been primaeval. And it is 

 possible tbat tbe Alcyouaria will be found to exbibit a bistory analogous 

 to tbat of Fisbes. In tbe present state of our knowledge tbe case must 

 be left bare. It is to be boped tbat microscopists wbo bave tbe 

 opportunity of examining deposits tbat may contain Alcyonarian 

 spicules will not fail to look for tbem. 



* ' Handbuch der Palfeontologie,' i. p. 209. 



t By a curious error tiie figure of Acis guadahipcnsis is stated by Duchassaing 

 asd Bliclielotti to be " de gr. uat.," when it is clearly the "portion gro&sie de la 

 nieme esplce." Cf. figs. 14 and 15 of pi. i., Mem. Acad. Torino (2) xix. 



