100 Dr. A. Philippics Zoological Notices. 



minim je ? Palpi duo, elongati, 5-articulati ; articulo quarto 

 longiori, quinto brevi, acuminato. Coxce utriusque lateris 

 unitee, anticse duae in linea mediana quoque sese tangentes. 

 Pedes unguibus duobus uncinatis terminati. Vulva lamina 

 Crustacea granulata cincta. 



Plate IV. Fig. 4. Pontarachna punctulum, Phil. Drawn magnified sixty 

 times. 

 g. Nat. size. 

 Fig. 5. The body beneath, magnified ninety times. 



d. The palpi. 



e. The coxae. 



/. The plate surrounding the fissure of the generative organs. 



7. Desmophyllum Stellaria, Ehrenberg. (Plate IV. fig. 6.) 

 The genus Desmophyllum, established by Prof. Ehrenberg 

 in the Memoirs of the Berlin Academy, is not less remark- 

 able by the characters of its calcareous stem, which is con- 

 stantly unramified, and has fascicularly united lamellae of the 

 star (Sterne), than by its animal. In this the surprising thin- 

 ness of the mantle is above all remarkable, which seems to be 

 entirely missing, so that we can most distinctly perceive 

 through it the cells at the margin of the star, nay, even the 

 slightest roughness of the surface. Indeed the animal mass 

 is in proportion to the calcareous mass a true minimum, and 

 so retracts itself on the contraction of the animal into the cavi- 

 ties of the lamellae, that I regarded the individual I received 

 in this state for the mere house, long before deprived of its in- 

 habitant. I have likewise observed the same on Cladocora 

 cespitosa, Ehrenberg [Caryophy Ilia, Lamk.), while the ani- 

 mal mass of Cladocora {Caryophy Ilia) Calycularis is far more 

 considerable, and even on drying remains as a pretty thick 

 membrane. When the animal of Desmophyllum Stellaria has 

 fully expanded itself, it projects about a line above the star, 

 while the border to a good breadth seems to be without any 

 animal envelope. The yellowish coloured oval mouth, sur- 

 rounded by an inwardly and outwardly folded lip, is distinctly 

 perceptible. True tentacula are missing; a greenish fleshy 

 mass extends from the mouth to near the margin of the star, 

 and is there drawn out into several folds, at the apex yellow- 

 ish, which, however, do not evince any definite arrangement, 

 yet generally exhibit two rows. When the folds are most di- 

 stinct they project at the furthermost only |rd of a line; greater 

 I have never seen, although I have preserved the animal alive, 

 and observed it for several days. By this want of true ten- 

 tacula the genus differs, likewise with respect to the animal, 

 very essentially from Cyathina, Ehrenberg, where the tenta- 

 cula are very regular, filiform, and orbiculate (geknopft). All 



