354 Dr. R. Koeliler on the Littoral Fauna of the 



The EcHiNODERMATA are chiefly represented by Spatangi 

 and Echinocardium jiavescens, MiilL, which are buried in the 

 sand to a depth of about 4 inches. Their position is easily 

 known by means of the little cone of sand which covers it. 



Echinocardium jiavescens attains a remarkable size ; the 

 largest are not less than about 3 inches long by 2^-2| inches 

 wide. They differ from the Mediterranean specimens in the 

 first place by their size and also by their coloration, which is 

 dark grey, never rose-colour, so that the name of AmyMdetus 

 roseus would not be applicable to them. Upon these specimens 

 I find small pedicellarias with fleshy valves, of a dark red 

 colour, which I liave indicated upon the Echinocardia of the 

 Mediterranean. At Herm the Echinocardia are rather less 

 frequent than the 8])atangi. Synajytm {S. inhcerens) are very 

 abundant. 



A Nemertian of very large size lives in these shell-sands ; 

 its body, of a dark colour, nearly black, exce])t at the anterior 

 extremity, which is lighter, is flattened and about yx, inch 

 wide and of considerable length. An imperfect specimen 

 which I extracted with much trouble was about 20 inches 

 long ; it broke up spontaneously and immediately into a great 

 number of small fragments, just as the Synaptm do. This 

 Nemertian is evidently very nearly allied to the species from 

 the Pouliguen which Giard has described under the name of 

 Avenardia Priei^ if indeed it is not specifically identical there- 

 with. All that the learned Professor says of that species 

 applies to the animal from Herm ; he has remarked that 

 " when taken out of the water, instead of stretching itself 

 softly like Lineus, the animal breaks up very rapidly into a 

 multitude of smaller and smaller fragments. When the 

 division ceases the fragments are scarcely more than 2 centi- 

 metres [about xij inch] long, and each of them has acquired a 

 rounded form, in consequence of the contraction of the muscles, 

 which gradually diminishes the fresh surface of the section, 

 and finally causes it to disappear entirely,*' — phenomena which 

 I have observed in the Herm Avenardia. 



Of the PoLYCH^TA, besides Nephtliys Homhergii, Artcia 

 Cuvieri, Arenicola piscatorum, and Sthenelais Edwardsii^ 

 some interesting species live in the sands of Herm. I may 

 mention a large (Jlycera which I refer to G. alba, Eathke, 

 and which is very frequent, as also numerous Clymenians : — 

 Clymene lumhricoides, Aud. & Edw., Leiocephalus coronatus, 

 Quatref., and Arenia cruenta and A. fragilis, Quatref. In 

 somewhat muddy places, near the portion covered with Zos- 

 tera, I have also taken some examples of Ammotrypane 

 Oistroides, Rathke. Among the Tubicola, TereheUa conchilega, 



