There appear to be about 7 articulations in the palpus itself, above the basal joint, marked by swellings upon its tubular stem, which is 1 line in diameter. [Illustration: Fig. 9.--A restored composite of _Isotelus maximus_ and _I. latus_. The exopodites are left out because entirely unknown. Drawn by Doctor Elvira Wood. Natural size.] Desiring to know more of this individual, I wrote to Doctor Bather and was surprised to learn that the specimen which was the basis of Woodward's observations is so badly preserved as to be of no real value. With his permission, I append a note made by Doctor Bather some years ago when selecting fossils to be placed on exhibition: _Asaphus gigas_ Dekay. Ordovician, Trenton Limestone. N. America, Canada. Descr. H. Woodward, 1870, Q. J. G. S., XXVI, pp. 486-488, text fig. 1, as _Asaphus platycephalus_. Coll. and presd. J. J. Bigsby, 1851. Regd. I 14431. This specimen is in the Brit. Mus. Geol. Dept. I 14431. The supposed hypostome is exceedingly doubtful; it lies dorsad of the crushed glabellar skeleton. The "appendage" is merely the edge of a part in the head-shield; the maxilla is some calcite filling, between two such laminæ. 13 Sept. 1911. (Signed) F. A. BATHER. Walcott figured a slice of _Isotelus gigas_ from Trenton Falls, New York, which shows a few fragments of appendages, but is of particular importance because it shows the presence of well developed appendifers beneath the axial lobe. =Isotelus arenicola= Raymond. Illustrated: Ottawa Nat, vol. 24, 1910, p. 129, pl. 2, fig. 5. The following quotations from my paper are inserted here to complete the record of appendage-bearing specimens: A rather remarkable specimen of this species was found by W. C. King, Esq., on the shore of Lake Deschenes at Britannia [near Ottawa, Ontario]. This specimen is an impression of the lower surface of the trilobite, and shows a longitudinal ridge corresponding to the central furrow along the axis of the ventral side of the animal, ten pairs of transverse furrows, and the impression of the hypostoma. The doublure of the pygidium has also left a wide smooth impression, but in the cephalic region the hypostoma is the only portion of which there are any traces remaining. The specimen was found on a waterworn surface of the beach, partially covered by shingle....