NEW ESSEX MARINE FISHES. 8l 



The examples of Nevitina fluviatilis were small, but the 

 coloration, though not brilliant, was well developed. Lintnaa 

 pereger, though common, was dwarfed, 12 mm. being the 

 height of the largest example. Bithynia tentacidata and B. leachii 

 were scarce and dwarfed. Ancylus fiuviatilis was very common 

 and of average size, whilst its ally, Velletia lacustvis, was dwarfed. 



The differences between the development of the various 

 species no doubt arises from the relative abundance of food, and 

 it is evident that these mollusca can exist without light. 



If, as is probably the case, other water-mains which are still 

 in use contain a like abundance of molluscan life, it must consti- 

 tute a standing danger to the population using the water drawn 

 from such sources. 



Mons. A. Locard'-^ has published a long list of species (so- 

 called) of mollusca from the water-mains of Paris, and all the 

 species that we have recorded are in his lists. 



NEW ESSEX MARINE FISHES. 



IN Dr. Laver's catalogue of the Fishes of Essex in the first 

 volume of the Victoria History^ several species are included 

 which were not known locally when the Maminals, Reptiles and 

 Fishes of Essex was published in i8g8. It seems desirable to 

 record these here for convenience of reference. We therefore 

 make the following extracts from the History : 



Famzlv DISCOBOLI. 



Lepadogaster bimaculatus, Penn. Double-Spotted 

 Sucker. — Has been rarely recognised, but there is [? was] one 

 specimen in the Brightlingsea Marine Station, caught in the 

 mouth of the Colne. 



Family BLENNID^. 



Blennius gattorigine, Bloch. Gattorugine. — Mr. E. A. 

 Fitch records the capture of one specimen in the Blackwater, off 

 Stangate, in August, 1898. (See Essex Nat. xi., p. 143). 



Family GADID^. 

 Gadus minutus, Linn. Power or Poor Cod. — Mr. E. A. 

 Fitch says that this is not rare at times in the Thames Estuary. 



2 A. Locard " Malacologie des Conduites d'eau de la ville de Paris." Mem. Acad. Sci. 

 Lyon. Scr. III., Tom. II. (1893), pp. 341-416. 



