_Specific characters._ Shell rounded, umbilicate, spire depressed, last whorl sometimes subangulate, whorls 6 to 6½, peristome oblique, little deflected above; labium thin, reflexed, thickest below; acute. Color dark brown or olivaceous, with a broad black band between two yellow ones, half hidden on the spire, lips white; within a fine purple with two white bands. Epidermis shining, polished below, the lines of growth faintly visible, sometimes very lightly malleated, and with spiral ridges; above with crowded scars bearing very short bristles in the young shell which fall off in the adult. _Animal_ slate colored, body cylindrical, rugose, tentacles moderate; foot elongated, behind wedge-shaped. _Shell_—large diameter 0.96 to 1.20; smaller diameter 0.76 to 0.96; height 0.42 to 0.54 hundredths of an inch. _Hab._ Santa Cruz, Cal., among decayed trees in the dampest places. This beautiful species is quite rare, only three adult and twelve young specimens having been found after long searching. It will probably occur more commonly in some part of the redwood forests which I have been unable to explore. It approaches nearest to _H. Dupetithouarsi_ and _H. fidelis_, being between them in form and size as well as colors, but the pilosity at once distinguishes it. Its distinct bands and rounded whorls separate it from _H. infumata_ and _Hillebrandii_, the latter when perfect having also much longer hairs. The animal is lighter colored than those of _H. arrosa_, _Nickliniana_, _redimita_, _ramentosa_, _tudiculata_, (which are all very similar) but much darker than that of _Dupetithouarsi_, and I believe also of _fidelis_ and _infumata_. The form of the shell is a link connecting these with _Mormonum_. In the tabular arrangement adopted in my State Survey Report, it would come in as the pilose analogue of _H. Dupetithouarsi_, and _H. exarata_, which are also its nearest geographical neighbors, as follows: =====================+====================+==================== § =A.= Shining; | § =B.= Dark; | § =C.= Brown; band triple, | hirsute in | band single, not rugose, | the young, | rugose, sculptured, l. whorls 6 to 8. | l. whorls 6 to 6½. | l. whorls 6 to 7. ---------------------+--------------------+-------------------- H. fidelis. | H. infumata.[24] | H. arrosa. H. Traskii.[25] | H. sequoicola. | H. exarata. H. Dupetithouarsi. | H. Hillebrandii. | H. Ayresiana. ---------------------+--------------------+-------------------- Judging from the form of _H. Mormonum_, it is possible that the young will be found to be hirsute.