388 P. HERBERT CARPENTER. 



pinnules of Actinometra meridionalis and Act. pauci- 

 cirra, which occur at the same localities. The contrast 

 between the pinnules of the two genera is so striking that 

 there must be some reason for it, and I am altogether unable 

 to understand why it should appear at all if the sacculi are 

 only vegetable parasites. 



I much doubt, therefore, if we are any nearer to an under- 

 standing of their real nature than we were before Vogt and 

 Yung took up the subject. 



Since the above lines were written another view of the 

 nature of the sacculi has been published by Walther,^ who 

 says : " Seine Function ist nach der mir zuganglichen Literatur 

 noch unbekannt, doch vermuthe ich auf Grund folgender 

 Beobaciitungen : starke Lichtbrechung, starke Farbstoffauf- 

 nahme. Mangel einer zelligen Structur, Aufbau aus poly- 

 gonalen oder rundlichen Plattchen, Lage an den Punkten 

 starkeren Wachsthums und eine gewisse fremdartige Einla- 

 gerung im Gewebe — dass es Reservematerial (Nahrungsdotter) 

 ist ; wahrend ich eine secretorische Function wegen der 

 umgebenden undurchbrochenen Kapsel fiir ausgeschlossen 

 halte." 



I have no remarks to offer respecting this suggestion of 

 Walther's ; but I will conclude by a few words upon Professor 

 Perrier's latest utterances upon the subject of the sacculi. He 

 attributes the name to me,^ being apparently unaware that it 

 originated with my father, as did also the idea that they might 

 be sensory organs.^ The latter view is also attributed to me 

 by Perrier in the following passage,* which refers to my first 

 publication on the subject of the Criuoidea in 1876. "Les 



1 " Untersuchungen liber deii Bau der Crinoiden, &c.," ' Palgeontographica,' 

 1886, Bd. xxxii, p. 165. I propose at some future time to make some remarks 

 upon this author's application of " Transcendental Morphology " to the Cri- 

 noidea. 



2 '• Memoire sur I'organisation et le Developpement de la Comatule de la 

 Mediterranee," ' Nouv. Archiv. du Mus. Hist. Nat./ 1886, 2n>e Ser., T. ix, 

 p. 154. 



» ' Proc. Roy. Soc.,' 1876, vol. xxiv, p. 227. 

 " Op. cit., p. 133. 



