110 COLEOPTERA 



DYTISCUS. 



marginalis. L. Occasionally in ponds. 



ACILIUS. 



sulcatus. L. Common. 



GYRINID-2E3. 



GYKINUS. 



natator. Scop. Common, 

 marinus. Gyll. Common. 



OEECTOCHILUS. 



villosus. Mull. By Dove and Trent. 



HYDROPHILIDiE. 



HYDKOBIUS. 



fuscipes. L. Common in ditches. 



HELOCHAEES. 



lividus. Forst. Ditches, 

 punctatus. Sharp. Ditches. 



PHILHYDRUS. 



nigricans. Zett. Ponds and ditches, 

 melanocephalus. 01. Ponds and ditches, 

 marginellus. F. Willington Pits, 

 suturalis. Sharp. Willington Pits. 



ENOCHRUS. 



bicolor. Pk. Pond at Findern. 



