INYERTEBRATA, ORYPTOGAMIA, MICROSCOPY, ETC. 263 



two groups can only bo regarded as liiglily analogous structures, for 

 the great variations in the number and disposition of these organs 

 lead us to question how far it is possible to demonstrate their homo- 

 logous natui-e, even within the limits of each separate phylum ; there 

 is, for example, no evidence which justifies us in regarding the eyes 

 of spiders and of imaginal insects as strictly homologous. The 

 author concludes by pointing out that the eyes of the Cephalopoda 

 present analogous arrangements. 



Chgetopoda of the Virginian Coast.*— Mr. Webster gives an 

 account of the Chaetopod Annelids collected by the zoological 

 expeditions sent out in 1874 and 1876 by Union College ; fifty-nine 

 species were obtained, which belonged to forty-nine genera and 

 twenty-three families. The following forms new to science were 

 obtained : — Lepidonotus variabilis ; Antinoe parasitica ; Lepidametria 

 commensalis (this is a new genus allied to Halosydria and to Lepi- 

 dasthenid) ; Phyllodoce fragilis ; Eumida maculosa ; SjjUis fragilis ; 

 SphcerosylUs fortuita ; Pcedophylax dispar ; Procercea tardigrada ; 

 P. ? (? Autolytus) ccerulea ; Nereis irritabilis ; Drilonereis longa ; 

 Staurocephalus sociahilis ; Spiocha:topterus oculatus ; Nerine heteropoda ; 

 Polydora liamata ; P. cceca ; Aricia rubra ; Aricidea fragilis (nov. gen. 

 et nov. spec.) ; Labellaria varians ; Pectinaria (Lagis) duhia ; Melunia 

 maculata ; Lysilla alba ; Potamilla tortuosa. Two new genera incertce 

 sedis are also formed ; one for a specimen in which the sides of the 

 head are produced into thin plates, which are covered with papillfe, 

 Cabria inccria ; in the other the head is divided into palpi, and the 

 elongate body is flattened and composed of a number of segments, 

 Phronia tardigrada. 



Adaptation and Mimicry in the Turbellaria.t — M. Paul Hallez 

 states that Leptoplana Iremellaris is able so to contract itself when 

 the stone that hides it is turned, and is so capable of taking on tho 

 character of surrounding bodies, that while he, with an educated eye, 

 has in a day taken twenty specimens, some of his friends have only 

 found two or three. Hyjihostomuin viride and other forms which contain 

 chh)rophyll-granules in their integument live among fresh-water 

 confervae. At Wimcreux there are two species of Vorticcros, one of 

 which is yellow, and lies among Bugulaj or Campanulariro, and tho 

 other red and a dweller among red algic. Planar ia nigra is best 

 found where deposits are black and putrid, and tho same is the case 

 with MesosloMum personatum. The more or less transparent species, 

 such as M. lactenin, live on stones or plants, but are protected by tho 

 colour of the object wliich supports them shining through their bodies. 



It very ordinarily happens that tho change in colour is accom- 

 panied by other mudifications ; taking the case of Vorticcros, wo find 

 that V. j^ulchcllum, which lives at greater dejiths than V. Schmidlii 

 (nov. sp.) is provided, as is so frec^uently tho cuso in pelagic as com- 

 ])ared with littoral species, with two long tentacles. Among tho 

 Planaria, P. nigra and P. fasca have fresh-water varieties. The 



* 'Trans. Alhaiiy Iii.st.,' ix. (1K70) p. 202 (11 plaits), 

 t ' liev. lutoruat. fcjci.,' iv. (1870) p. 3G2. 



