70 THE NAUTILUS. 



canal in the spring, it is a fine place for unios, such species as 

 Anodonta salmonia, A. benedictii, Alasmodonta marginata, A. del- 

 toidect, Unio 'gibbosus, Anodontopsis ferussacianus, Quadrula plicata, 

 Q. undulata, Ldmpsilis gracilis, iris, nasutus, luteolus, ventricosus, 

 rectus, alatus, and cariosus being found in great abundance and 

 beauty ; the bottom is covered knee-deep with black mud, affording 

 a fine retreat for the mussels. 



The Genessee River, both above and below the falls, affords good 

 collecting, the unios being abundant above and the gastropods below 

 the falls. The characteristic species above the falls are Alasmodonta 

 marginata, A. rugosa, A. pressa, Quadrula rubiginosa, Lampsilis 

 iris, L. luteolus, L. alatus, Sphcerium simile, S. stamineum, S. trmis- 

 versutn, Limncca palustris, Planorbis trivolvis, Physa lieterostropha, 

 Goniobasis livescens and CampeloWm decision, while those below are 

 Sphcerium transversum, Limncea catascopium, Planorbis trivolvis, 

 Physa lieterostropha, and Bythinia teritaculata. 



Both the east and west banks of the Genessee River below the falls 

 are good localities for mollusks, about the same species being found 

 as on the Pinnacle, -with the addition of Pupa muscorum, Circinaria 

 eoncava, Vallonia pulchella, V- costata, Polygyra thyroides, P. hirsuta 

 and P. palliata. The wooded banks of Seneca Park afford good 

 retreats for mollusks, and they may be found here in great abundance. 

 One of the pleasantest trips near Rochester is to Irondequoit Bay, 

 an inlet from Lake Ontario, five miles long and about one in breadth. 

 The hills about are from 100 to 200 feet high, and the water has a 

 maximum depth of 80 feet. Mollusks are correspondingly numerous : 

 Spharium simile, S. transversum, Succinea ovalis, Limncea palustris, 

 L. desidiosa, Planorbis campanulatus, P. trirolvis, P. bicarinatus, P. 

 dejlectus, P. parvus, Segmentina armigera, Ancylus tardus, Physa 

 heteroslropha, Pleurocera subulare, Goniobasis semicarinata, Bythinia 

 tentaadata, Amnicola lustrica, Yalvata sincera and V- tricarinata 

 are found in great abundance along the shore or living on the lily 

 pads. The wooded banks yield the common helices in great 

 abundance. 



The best fresh-water beach collecting which the writer has ever 

 experienced is to be found at Charlotte and Summerville, on Lake 

 Ontario, the former on the west and the latter on the east side of the 

 mouth of the Genessee River. There is always a line of " sea* 

 wrack " which is alive with fresh-water mollusks. Here we have 



