72 Notes on Certain Terrestrial Mollusks. 



follows : "I have two more specimens of the Myiarchus 

 (No. 1555) in my possession (which I hope soon to send 

 yon), and consider them distinct from M. lawrencii. These 

 two specimens, like the one yon have seen, have a grayish- 

 white throat, and on the breast deeper longitudinal spots, 

 although slightly marked, and the bill also broad. The 

 physiognomy of these birds in life is sufficiently distinct 

 from M. I'lwrencii, to enable me to distinguish them even at 

 a distance ; the body of No. 1555 is in fact thicker and more 

 robust. I have had occasion to kill a great many of the M. 

 lawrencii, and I have always been able at first sight to re- 

 cognize them as such, although perched at a great height. 

 My immediate impression on seeing No. 1555 for the first 

 time was that I had before me a new form. I have never 

 seen in the M. lawrencii dark ilammulations on the breast, 

 which the three specimens of No. 1555 show, although but 

 lightly marked." 



VIII. — Notes on Certain Terrestrial MollusJcs, with Descrip- 

 tions of New Species. 



BY THOMAS BLAND. 

 Read Oct. 5, 1S74. 



Oleacina flexuosa. Pfr. 



This was described in 1854 (Zool. Proc.), from a speci- 

 men in Cuming's cabinet, and subsequently figured in Nov. 

 Conch., I, t. 3, f. 16-17, but the habitat was unknown. 



There is in the Swift cabinet* a very fine example, with 



*I have recently had the opportunity of examining the collection of my late 

 esteemed friend, Mr. Robert Swift, before its delivery to the Philadelphia Academy, to 

 which it has been presented by his daughter. 



