H. R. SYKES—-REPORT ON THE POLYPLACOPHORA. 33 
A good series was collected, which vary considerably in their colour pattern : 
the green pores from which the tufts arise are very conspicuous in spirit 
specimens. 
ACANTHOCHITES PENICILLATUS (Deshayes). 
Chiten pencillatus, Deshayes, Moll, Réunion, p. 41, pl. vi. figs. 8-10. 
Acanthochites penicillatus, Deshayes; Pilsbry, Man. Conch, vol. xv. p. 15, pl. iv. fig. 84, 
pl. viii. figs, 29, 50. 
Hab, Shores of Chaki Chaki Bay, Pemba Island. 
A single specimen, identified from a shell, collected by Robillard at 
Mauritius, and presented to me by Mr. Sowerby. I now feel some doubt 
whether I was correct in referring * to this form, specimens collected in the 
Gulf of Manaar. At that time I had not seen the ‘ Robillard’ shell. The 
figures that I then gave were not good. A single shell of an Acanthochitoid 
from ‘* Wasin, 10 fath.” may belong here, but is too young for accurate specific 
determination. There is also a very young shell from “shore at Zanzibar ” 
which I think belongs here; it shows the fringe of glassy spicules at the 
periphery most distinctly. 
CRYPTOPLAX BURROWI (Smith). 
Chiton ( Chitonellus) burrowt, Smith, Zool, ‘Alert,’ p. 85. 
Cryptoplax burrowt, Smith; Pilsbry, Man. Conch. vol. xv. p. 54. 
Flab. Wasin, Fast Africa. 
A single specimen, which the author of the species has very kindly examined, 
Hitherto recorded from Australia and the Straits of Macassar. 
_ CRYPTOPLAX sTRIATUS (Lamarck). 
Chitonellus striatus, Lamarck, Anim. sans Vert. vol. vi. p. 317 (1819). 
Cryptoplax striatus, Lamarck ; Pilsbry, Man. Conch. vol. xv. p. 58. 
Hlab. Zanzibar, on reet edge, east coast; also 10-20 fath. in Zanzibar 
Channel, and on the shore. Khor Dongola, washed out of nullipore dredged 
in 5 fath. just west of Beacon Islet. 
After a careful examination of the specimens, as also the separated valves, 
I am unable to sever the form from this well-known species, which has been 
recorded from various Australasian localities. In a note some few years ago tT 
T recorded the occurrence of the genus in Natal, and I think the specimen then 
figured, whose specific standing I was unable to be sure of, really belongs to 
C, striatus. Save for the last mentioned notes, the present paper appears to be 
the only record of the genus having been found on the shores of Africa. The 
record from Khor Dongola is referred here with some little doubt as the single 
specimen is very young. 
I * Rep. Oyster Fisheries, pt. 1, Suppl. Rep. iv. p. 179. 
+ J. Malac. vol. vii. p. 164 (L900). 
LINN. JOURN.— ZOOLOGY, VOL. XXXI, 3 
