34j3 On the Great Mastodon. 



of a moist white dust. The head bears four antennae. There 

 are seven feet on each side, and a double appendage. The ge- 

 neral colour is a dirty white. I have obtained from some indi- 

 viduals five young ones completely formed ; from others fewer ; 

 but a peculiarity worthy of notice here presents itself, namely, 

 that I have seen some bearing eggs in different stages of deve- 

 lopment. The eggs and the young pass out by a triangular 

 opening, situated about the middle of the ventral surface. The 

 transparency of the crust admits of the young and the eggs be- 

 ing seen before they leave the body of their parent. 



" To know our enemies is the first step — ^^to determine the 

 means of ejecting or destroying them is the last. To the latter 

 point I have directed my attention, and have made some expe- 

 riments bearing upon it. It would be very useful to have a po- 

 lice established in our ports, with the view of watching and pre- 

 venting the devastations of these animals." 



Critical Notices of various Organic Remains hitherto discover- 

 ed in North America. By Richabd Harlan, M. D. * &c. 



The author of the following observations has been led to the 

 undertaking by the urgent requests of many of his scientific 

 friends in Europe. 



It will appear in the ensuing pages that many eminent Ame- 

 rican naturalists have occupied themselves in the successful pro- 

 secution of this most interesting department of human know- 

 ledge ; and yet very recent inquiries have satisfied us, that but 

 a small fraction of what has been published on this subject in 

 this country is adequately known to foreign naturalists. With 

 the exception of some few of our scientific journals, the limited 

 circulation in foreign countries of our scientific publications, is 

 a subject of just complaint among Europeans, who interest 

 themselves in works of this nature. We have been honoured 

 with the personal acquaintance of hundreds of transatlantic sa^ 

 vans, to whom we are well assured the following pages, imper- 

 fect as they necessarily are, will prove an acceptable offering ; 



• From the sheets of the volume of the Transactions of the Geological So- 

 ciety of Philadelphia, at present in the press, sent to the Meeting of the 

 British Association at Edinburgh. 



