154 PEOCEEDINGS OF THE MAIACOLOGICAL SOCIETY. 



Mr. Crossland describes specimens, which probably belong to this 

 species, under two headings, here called A and B, adding that the 

 two sets are very much alike but differ in details of coloration. 



A. "When crawling almost vermiform, foot tapering, but no tail. 

 Tentacles longer than rhinophores. Rhinophores short and perfoliate ; 

 yellowish white ; in one specimen a little yellow colour basally. 

 Foot expanded and grooved in front, but not drawn out. Ample 

 margins laterally. Cerata regularly tapering and curved ; set in 

 rather oblique transverse rows. Ten rows in all, but, seen from the 

 side, the cerata spread out fan fashion. Body and appendages 

 sprinkled with white specks ; transparent, so that pink organs in body 

 and slender brown liver diverticula show through. A little pink 

 colour about mouth. Collected under a stone and from bottom of 

 Ughter." 



B. "Under a stone from the shore. Tentacles and rhinophores 

 about the same length. Latter with about 10 distinct perfoliations. 

 Body slender, cerata long. Foot narrow, dilated and grooved in front, 

 but corners not at all drawn out. Cerata in six transverse rows. 

 The largest cerata are the median ones of the third set. Formula of 

 arrangement : — 



„ „ I close together. 



5 5 



4 4 



2 2 



1 1 



Body largely colourless and translucent. Large light lilac patch on 

 head between tentacles and rhinophores. Light tint of same on distal 

 half of tentacles. Distal half of rhinophores yellow. Row of large 

 yellowish white blotches along back. A pair of orange yellow streaks 

 on the head. Liver light brown. 



" The animal is very active." 



The largest specimen belongs to set A. It is not much more than 

 12 mm. long, but somewhat bent, and about 4-5 broad. The smaller 

 specimens are more slender in proportion. As a rule the cerata are 

 set in about six groups, but, in the largest, only four are distinct, the 

 remaining cerata being crowded together on the tail. The first, third, 

 and fifth rows, generally, are inclined somewhat towards the head, the 

 second, fourth, and sixth, somewhat towards the tail, but the cerata do 

 not seem to be arranged in definite horseshoes, as in some forms. The 

 rhinophores and tentacles are both short, the former strongly perforate. 

 The anal papilla is situated on the side, behind the .second row of 

 cerata. The genital orifice lies in front of it, under the first row. 

 The foot is rounded in front. 



The pale yellow buccal mass is somewhat flattened and compressed. 

 The jaws bear fine but rather irregular denticles on the edges. There 

 is some discrepancy in the statements of previous authors as to the 

 presence or absence of these denticles. It is probable that the edge of 

 the jaw is originally denticulate, but becomes worn smooth with age. 

 The radula consists of 14 pectiniform teeth. They are not bilobed, but 



