Parv. 



600 



size; showing varieties 

 of border ; fig. 1 b, 1 c^ 

 broader and longer 

 forms of tail piece ; 1 e^ 

 large chin piece (hypo- 

 stoma, attached to fron- 

 tal doublure of head ; 

 plate 9, fine large speci- 

 men in Boston Soc. Nat. 

 Hist, museum (omitted). 

 Braintree formation. 

 Middle Cambrian, M,C, 

 — Note Thousands of 

 specimens are supposed 

 to have been dumped 

 into Boston harbour in 

 making Long Wharf. 

 Green's original speci- 

 men had no known 

 locality and was con- 

 jectured to be a Euro- 

 pean specimen accident- 

 ally mixed up with his 

 American collection. 

 Cashier Wentworth was 

 the first to suspect that 

 the forms might be 

 trilobites; Charles T.Jackson the first to recognize them as 

 Paradoxides ; W. B. Rogers the first to visit the locality, col- 

 lect and describe them at the next meeting of the society. 

 Paradoxides kjerulfl. Linnarsson; used by Walcott, in 



M,Q- 



1 2^ Bull. No. 30, U.S. G.S.page 178, plate 

 ^ 20, fig. 2, to explain a feature of the 



Rocky Mountain species Paradoxides 



\ gilherti {M. C\ Middle Cambrian of 



\ Sweden) viz. the small round protube- 



■' ' ' ranee between the eyes and the gla 



bella ; a character observed by Ford in the young of Olenellus 



asaphoideSy P. gilherti embryonic features last to an age long 



after they disappear in other species; normal individuals also 



