Ib94. ] NATUKAL SCIENCES OF PHILADELPHIA. 161 



specimens. Tliey are also grayer than specimens from Indian River 

 loaned me by Mr. G. S. Miller, Jr. They are likewise much larger, 

 as the following table of measurements will show : 



In hispidus the ratio of total length to zygomatic width is 56-5 in 

 littoraUs 57*2, in the Tarpon Springs specimens 51 •4. 



A later specimen from Mr. Dickinson is very similar in every fea- 

 ture to typical hispidus from North Carolina, being browner than 

 typical littoraUs and quite as small, though nearly adult. The receipt 

 of this specimen has induced me to defer separating the southwestern 

 form until a large series is at my disposal from this region. These 

 two gray Cotton Rats from Tarpon Springs are either abnormally 

 large and the small one abnormally brown, or else there are two 

 species, the smaller, true hispidus, the larger, unnamed. Such a con- 

 dition of affairs is not impossible, the former being an inhabitant of 

 the inland fresh watei- marshes, the latter frequenting the maritime 

 shores. 



22. Eeithrodontomys humilis (subsp?) And. i^c Bach. Harvest Mouse. 



One si)ecimen received. I do not find any record of this mouse 

 from Florida. The specimen, if characteristic of the form inhabiting 

 southern Florida, represents a race as different from the northern 

 type as other of the Florida Muridte. 



The specimen, while apparently full grown, is not fully adult and, 

 in the hope of securing more specimens, further description is now 

 deferred. 



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