Lewis & Short

monstrĭfer, fĕra, fĕrum, adj. [monstrum-fero],

  1. I. monster-bearing, that produces monsters (poet. and in post-Aug. prose): campi, Val. Fl. 5, 222: novercae, i. e. Juno, who sent monsters to Hercules, id. ib. 5, 43: sinus (i. e. mare), id. ib. 2, 498: antra, Claud. Stil. 2, 110.
  2. II. Monstrous, horrid, misshapen: animalium hominumque effigies monstriferas, Plin. 6, 30, 35, § 187 (but the better reading is monstrificas).