HEMPIIILLIA. 



247 



Fig. 144. 



H. glanrlulo.sa, contracted 

 in spirits. 



Fig. 146. 



Internal 

 shell of 

 H. glan- 

 dulosa. 



Jaw of 

 H. glandulosa. 



slightly reflected over the edges of the shell. No distinct locomotive disk to 

 foot. Lines of furrows run near and parallel to edge of foot, rising above the 

 extremity and apparently uniting over a transverse 

 mucus slit, overhanging which is a greatly produced horn- 

 shaped process. Respiratory orifice at right edge of 

 mantle, near its centre. Generative orifice at right 

 side of neck, near right eye-peduncle. 



Shell external, not spiral, its edges imbedded lightly 

 in the mantle, very thin, unguiform, almost as large 

 as the mantle (in specimens preserved in alcohol). 



Jaw wide, low, slightly arcuate ; ends blunt, but little attenuated ; anterior 

 surface with numerous ribs denticulating either margin (Fig. 146). 

 Lingual membrane described below under 

 H. glandulosa. 



Oregon Region, at Astoria. 



This curious slug, by its general outline 



and by the form and position of^its shell, 



may be compared to Omalonyx unguis 



D'Orb, and the species known formerly as 



Succinea appendiculata Pfr., but now usually referred to Amphibulima. 

 The former has, however, a jaw with the supplementary extension as in Suc- 

 cinea, the latter has the jaw usual in Bulimulus and Cylindrella, while neither 

 of them has the prolongation of the mantle. Both of those genera^also are 

 readily distinguished by their shell being more developed and approaching a 

 spiral form. 



Hyalimax is distinguished from HempTiillia by its Succinea-like jaw. Other- 

 wise, it resembles our genus in 'its general outward appearance, and by its non- 

 spiral shell. This shell, however, in Hyalimax is almost, if not completely, 

 internal, while the shell of Hemphillia is entirely exposed. 



Binneya, in its prolonged mantle and costate jaw, resembles Hemphillia, but 

 its shell is much more developed, spiral, striate and almost capable of protect- 

 ing, though not absolutely including, the animal when contracted. 



Xanthonyx and Simpulopsis are both described with costate jaw, but they 

 have both highly developed, decidedly spiral shells. 



Finally, from all the above-mentioned genera, and from all known sublimaci- 

 form genera, our genus is at once distinguished by the peculiar hump-like 



distinctus nuUus. Porus mucosns transversus in apice pedis, processu coniforme valido 

 protectus. Apertura respiratoria ad dextram, in medio niarginis inferioris pallii, genitalis 

 ad basin tentaculi dextri oculigeri. 



Testa externa, unguiformis, subquadrata, replicatura pallii marginorura breviter 

 inclusa. 



Maxilla et lamina lingualis ut in Arione constituta, dentes centrales tricuspidatae, 

 laterales bicuspidatae, marginales qnadratse, bicuspidatae, papillis internis valde produc- 

 tis, extemis subobsoletis. 



