FAUNISTIC NOTES AT PLYMOUTH DURING 1893-4. 221 
In November, 1892, among coralline from tide-pools, I repeatedly 
found specimens of a minute white Dorid, whose back exhibited a 
regularly arranged series of very spiny tubercles. I was completely 
at a loss as to its identification, until towards the end of the month 
several slightly larger specimens were taken, which showed traces 
of pigmentation,—brownish patches here and there, and a brown 
ring on each rhinophore. During the next month or two I followed 
out the growth of these little Nudibranchs by obtaining fresh speci- 
mens from the tide-pools from time to time, until I had a complete 
series between the minute and absolutely white form and the fully 
developed and highly pigmented Afgirus punctilucens. From these 
observations I am strongly inclined to regard the Algirus hispidus of 
Hesse as merely one of the younger stages of Mgirus punctilucens. 
They also enable me to identify, as a still earlier stage of the same 
species, a remarkable post-larval form which had occurred in the 
autumn tow-nettings, as observed both by Mr. Bles at Plymouth and 
Mr. Vallentin at Falmouth. It was simply one of these minute 
white Afigirus with the addition of a pair of large velar lobes, by 
means of which it swam freely in the water. 
Two other Gastropod larvee that I have noticed in the tow-nettings 
are worthy of record. One is the Hehinospira diaphana, figured in 
Bronn’s Thier-Reichs, and the other the Cirropteron semilunare of 
Michael Sars (Besk. og Jagttag., &c., Bergen, 1835). In each of these 
forms the velum is produced into ciliated lobes, three on each side in 
Echinospira, and two in Cirropteron. The former occurs in the 
summer tow-nettings every year; the latter I have only seen once, 
towards the latter end of August, 1893. 
Crustacea.—l'o my former record of Apseudes talpa I may add 
here the occurrence of Apseudes Latreilliv at Plymouth. I found 
numerous specimens in the mud around the roots of corallines from 
Drake’s Island in July, 1893, and on other occasions. 
In addition to the Schizopoda mentioned in my previous Notes, I 
have taken the following also at Plymouth :—Siriella frontalis 
(M. Edw.), Drake’s Island, among weeds, June 2nd, 1893, one speci- 
men. Siriella jaltensis, which occurred in the tow-nets at night in 
September, 1892, abundant on the shore at Drake’s Island among 
weeds, June 2nd, 1893. Heteromysis formosa (S. I. Smith), a few at a 
time only, Millbay Channel, New Grounds, Cawsand Bay, Yealm, and 
off Stoke Point. Leptomysis mediterranea, common in Cawsand Bay, 
June 5th, 1898. Leptomysis gracilis, October, 1893.  Hrythrops 
eleguns, October, 1892 and 1893. Mysidopsis gibbosa, Cawsand 
Bay, several occasions. Hemimysis Lamorne, Cawsand Bay, July 
oth, 1898. Macromysis imermis and M. neglecta, among weeds 
everywhere. Schistomysis arenosa, Cawsand Bay, Whitsand Bay. 
