No. 4.— Notes on the ontogeny of Paradoxides, with the description of 
a new species from Braintree, Mass. 
By Percy E. Raymonp. 
PaRADOXIDES harlanz is so large and striking a fossil, its occurrence 
is such an oasis in the sterility of Massachusetts palaeontology, and 
its discovery and subsequent history borders so closely upon the 
domain of romance, that it has become one of the most widely known 
of all the older invertebrate fossils. Although repeatedly described 
and figured and known from abundant material, the species has never 
been studied from the phylogenetic standpoint, and it has not, there- 
fore, been brought out how strikingly different this species really is 
from most of the other members of the genus. In studying the speci- 
mens from the viewpoint of an investigation of the growth stages and 
relationship to other forms, the writer has been forced to the conclu- 
sion that there are really two species present in the Hayward quarry 
at Braintree, and the new species is now named in honor of the Messrs. 
Hayward, father and son, who have long been proprietors of the quarry 
which has furnished these trilobites, and who have served science by 
the care with which they have conserved good specimens. 
PARADOXIDES HARLANI Green. 
Plate, fig. 3-6. 
Paradoxides harlani Green, Amer. journ. sci., 1834, 25, p. 336. W. B. Rogers, 
Proc. Boston soc. nat. hist., 1856, 6, p. 27-29, 40-44. Stodder, Ibidem, 
p. 369. W.B. Rogers, Amer. journ. sci., 1856, ser. 2, 22, p. 296, Edinb. 
New philos. jour., 1856, new series, 4, p. 301; 1857, 6, p. 314. C. T. Jack- 
son, Comptes rend. Acad. sci. Paris, 1856, 43, p. 883; 1858, 46, p. 254, Proc. 
Boston soc. nat. hist., 1859, 7, p. 54, 75. W. B. Rogers, Ibidem, p. 86. 
Ordway, Ibidem, 1860, 7, p. 427, 1861, 8, p. 1-5, fig. 2. C. T. Jackson, 
Ibidem, p. 58. Dana, Man. geol., 1863, p. 189, fig. 245. Walcott, Bull. 10, 
U.S. geol. surv., 1884, p. 45, pl. 7, fig. 3; pl. 8, fig. 1b, c, e, (non 1, la, 1d); 
pl. 9, fig. 1. Grabau, Occ. papers Boston soc. nat. hist., 1900, 4, p. 681, 
pl. 35, fig. 3 (after Walcott); pl. 36 (the type); pl. 37; pl. 38, fig. 1b, 
¢,e; non 1, la, 1d (after Walcott); pl. 39 (after Walcott). Shimer, Amer. 
journ. sci., 1907, ser. 4, 24, p. 178. Walcott, Smithsonian misc. coll., 
1910, 53, p. 254, fig. 12, 13, (non 10, 11). 
