THE LE PA DOG ASTER FAMILY. 199 



that there is no differentiation between them. The vent showed 

 only longitudinal rugae with the long median papilla pos- 

 teriorly. 



In July, forms of 26 and 82 mm. are obtained, and they 

 seem to be the continuation of the former series. The chief 

 changes are the increase of the fleshy folds of the lips superiorly 

 and inferiorly. The latter form a semicircular flap on each side, 

 with a posterior continuation, the former having the shape of a 

 broad and continuous flap. In the females the distinction 

 between the margin of the posterior division of the sucker and 

 its broad accessory flap is present. The papillae along the front 

 margin of the anterior division are also distinct in the same sex. 



In August, specimens of 22, 2.5, and 33 mm. from Lochmaddy, 

 North Uist, where this species is the prevalent form, are in the 

 collection. The smallest is thus only the length of that from 

 St Andrews in February, so that either the specimen had grown 

 but little, or had been hatched very late the previous season, 

 unless we are to suppose that very early deposition of ova occurs 

 in the Outer Hebrides. The former is the more probable. 



Adults of 53 and 54 mm. for females and 48 mm. for males 

 are met with in the same month, so that they would appear to 

 be at least in their second year. The chief sexual distinctions 

 externally appear to be the greater breadth and more mem- 

 branous condition of the frilled border in front of the anterior 

 division of the sucker in the male, — thus giving a larger surface. 

 Similarly the broad frill behind the posterior division of the 

 apparatus is increased, and its folds have not the regular and 

 definite pattern seen in the female. Moreover, the frill is 

 indistinctly separated from the sucker proper. The latter, in 

 short, has no free rim, but runs into the frill. The testes of the 

 male are small and compact, like those of the shanny. 



On the other hand, the female presents a somewhat thicker 

 rim at the front margin of the anterior division of the suctorial 

 apparatus, and the whole of the horseshoe shaped region is much 

 more papillose, even the folds between two of the rays laterally 

 being studded with papillae. The semicircle formed by the hind 

 edge of the posterior division of the apparatus stands out freely, 

 and is minutely papillose ; while the marginal fringe is composed 



