268 DR JOHNSTON'S DESCRIPTIVE CATALOGUE OF THE 



and margin of the lip whitish, the throat brown or purple. Length 

 j^ths; breadth T %ths. Turbo rudis, Flem. Br. Anim. 298. 



Var. a. Shell of a uniform pale dusky yellow, the spiral striae 

 impressed. Turbo rudis, Mont. Test. Brit. 304. Maton and 

 Rackety in Lin. Trans, viii. 159. tab. 4. fig. 12, 13. Lam. 

 Anim. s. Vert. vii. 49. 



Var. b. Shell a uniform flesh-red, the spiral strise often raised. 

 Turbo rudissimus. 



Var. c. Shell a uniform purplish red, the spiral strise raised 

 into sharp ridges. Turbo jugosus, Mont. Test. Brit. p. 586. 



Var. d. Shell white or with two dusky bands, the spiral strise 

 elevated into ridges. T. jugosus, var. Mont. loc. cit. 



Hob. On rocks at high-water mark or above it, abundant. 



This never attains one half the size of the preceding, and is certainly a very 

 distinct species, clustering in myriads in crevices of rocks at or above 

 the highest tides, and very rarely descending to the zone of the common 

 wrack (Fucus vesiculosus), which is the favourite walk of L. littorea. 

 All the varieties are to be found intermixed, but many excellent natur- 

 alists consider those on which the striae rise into ridges as distinct from 

 the smoother kind, an opinion which I do not adopt, believing that this 

 character may be dependent partly on age and partly on differences in 

 the external influences to which they have been exposed. The animal 

 is not streaked and spotted, but of a uniform colour with a dusky line 

 along the outer side of the tentacula ; and it is, as Mr Boys first stated, 

 viviparous, the females carrying their innuiuberable young, immersed in 

 a cluster of jelly and arranged in transverse rows, within the branchial 

 cavity, where they may be found at all seasons. The penis of the male 

 is very large, retroflected, linear-oblong, compressed, serrulate on the 

 outer side. Copulates in November ; and very small individuals may 

 be found in sexual union at this period of the year. 



3. L. saxatilis, shell subglobose with a small raised spire, regularly 

 chequered with square spots on a white or yellow ground, spirally 

 striate or grooved ; whorls four, rounded, the body very large ; 

 aperture dark purple with a pale margin. Diam. 2 lines. Bean. 



Hob. On rocks near low-water mark, which are bare of weed but covered 

 with Balani. 



Captain Brown, in his Illustrations of Conchology, has given, in plate 46, 

 two figures, No. 7, 8, of a variety of Turbo littoreus, which seem to have 

 been drawn from specimens of this species, but of a much larger size 

 than any I have seen. If a variety, it certainly does not belong to the 

 L. littorea but to L. rudis, with which it is found occasionally inter- 

 mixed ; but Mr Bean and Mr Alder, both very experienced concholo- 

 gists, consider it distinct. The latter remarks : " It is not uncommon 

 on rocks between high and low water mark, and in (what I take to be) 

 its full grown state, has the margin of the aperture nearly continuous, 

 with a slight depression behind it There is a black variety of it which 

 is very similar to T. tenebrosus ; but the latter species, so far as I know, 

 is never found on rocks, but always in muddy estuaries." 



4. L. petrcea, shell conical, the body ventricose and larger than the 



