Locomotory Appendages of Trilobites. 201 
tions of parts found which might belong to the Trilobites have little 
value, and were accepted as such by naturalists.’ ” 
In 1872, Dr. A. S. Packard, in his work on the Development of 
‘Limulus polyphemus, page 185, says: “Though disposed to regard 
the processes figured by Mr. Billiugs as feet, still the proof is unsatis- 
factory. The Trilobites probably had habits similar to those of 
Limulus, and consequently they must have had ambulatory feet, 
rather than phyllopodal feet, attached to the middle segments of the 
body. In view of the conflict of opinions as to the nature of the 
limbs of the Trilobites, it is to be hoped that the matter will not be 
suffered to rest here by paleontologists, even if the most unique and 
valuable specimens have to be sacrificed in making the requisite ob- 
servations.” 
In 1874, Mr. S. A. Miller figured and described, in the Quarterly 
Journal of Science, an ichnolite which he regarded as the track of 
Asaphus. ° In 1880, he reviewed the work of 1874, and figured and de- 
scribed another slab, the markings of which he regarded as made by 
an animal generically related to the former. 
In 1875, Prof. Dana, in his Manual of Geology, page 123, says: “No 
remains of legs are found with any Trilobites.’’ 
In 1876, Dr. Nicholson, in his Manual of Zoology, page 219, says: 
“No traces of ambulatory or natatory limbs, of branchie or of an- 
tennee, have ever been discovered. On the under surface of the body 
nothing has hitherto been discovered except the hypostoma or labrum. 
It has generally been supposed that the axial lobes protected a series 
of delicate respiratory feet; but this view is doubted by many 
authorities, and the question is one which we have at present no means 
of deciding.” 
{fn 1878, Prof. Huxley, in his Anatomy of Invertebrate Animals, 
page 220 (Am. Ed.), says: ‘‘ Limbs or appendages capable of effecting 
locomotion are always attached either to the head or to the thorax— 
the extinct Trilobites possibly form an exception to this rule.’’ Again, 
page 224: “ Now, among the water-breathing Arthropoda no trace of 
limbs has yet been certainly discovered among the Trilobites.” 
In the Encyclopedia Britannica, ninth edition (vide Crustacea), Mr. 
Henry Woodward, F.R.S., says: “ At present more evidence is needed 
as to the nature of the locomotory appendages of this extinct group— 
Trilobita.”’ 
In a letter from Mr. C. D. Walcott, dated June, 1883, he states that 
all his recent sections “simply corroborate the views given in his 
pamphlet of 1881.” 
