_Remarks._--Most measurements show a sexual dimorphism in this subspecies. Adult males are 15 per cent larger in external measurements except that the foot is approximately the same. Cranial measurements average approximately 5 per cent larger in males except that the breadth of the rostrum and length of the maxillary tooth-row are slightly less. South and east of Tacámbaro our specimens all were taken in dry semitropical country, where bananas and sugar cane were the principal crops grown. This subspecies has been recorded also from La Huacana, Michoacán, as well as from La Salada, the type locality, by Goldman (1911:39). =Liomys irroratus jaliscensis= (Allen) Northern Spiny Pocket Mouse; Spanish, Ratón Norteño _Heteromys jaliscensis_ Allen, Bull. Amer. Mus. Nat. Hist., 22:251, July 25, 1906, type from Las Canoas, approximately 20 mi. W Zapotlán, 7,000 ft., Jalisco. _Liomys irroratus jalicensis_, Goldman, N. Amer. Fauna, 34:60, September 7, 1911. _Range._--Northwestern part of state. _Specimens examined_, 3: nos. 120273-120275 (U. S. Nat. Mus.) from Zamora. _Remarks._--As explained in detail by Hall and Villa (1948:254) these specimens from Zamora are intergrades between _L. i. jaliscensis_ and _L. i. acutus_ and with almost equal propriety could be referred to either subspecies. =Liomys irroratus acutus= Hall and Villa Northern Spiny Pocket Mouse; Spanish, Ratón Norteño _Liomys irroratus acutus_ Hall and Villa, Univ. Kansas Publ., Mus. Nat. Hist., 1:253, figs. 4-6, July 26, 1948, type from 2 mi. W Pátzcuaro, 7,700 ft., Michoacán. _Liomys irroratus alleni_, Goldman, N. Amer. Fauna, 34:57, September 7, 1911, part. _Range._--Pátzcuaro and vicinity. _Specimens examined_, 16: nos. 100170-100184 and 50356 (U. S. N. M.), distributed, with reference to Pátzcuaro, as follows: 3 mi. NW, 6,700 ft., 1; 2 mi. W, 7,700 ft., 5; 2 mi. W, 6,700 ft., 2; Pátzcuaro itself, 1; 5 mi. S, 7,800 ft., 7. _Remarks._--None of the eight females contained embryos. Two adult males weigh, in grams, 71.5 and 65.1; the average and extreme weights for five adult females are 50.8 (44.8-61.8). =Liomys irroratus alleni= (Coues) Northern Spiny Pocket Mouse; Spanish, Ratón Norteño _Heteromys alleni_ Coues, Bull. Mus. Comp. Zoöl., 8:187, March, 1881, type from Río Verde, San Luis Potosí, México. _Liomys irroratus alleni_ Goldman, N. Amer. Fauna, 34:56, September 7, 1911. _Range._--Northeastern part of state. _Specimens examined_, 5: nos. 50325-50329 (U. S. Nat. Mus.) from Queréndaro. _Remarks._--The specimens from Queréndaro are not typical of the subspecies _L. i. alleni_ in that the shape of the interparietal bone and width of the basisphenoid bone are almost exactly intermediate between the conditions obtaining in typical _L. i. alleni_ and topotypes of _L. i. acutus_. =Reithrodontomys megalotis saturatus= Allen and Chapman Western Harvest Mouse; Spanish, Ratón Orejudo