Species: Hemphillia malonei

Prior to copulation, the slugs engage in a prolonged trailing phase from 45 minutes to 3.5 hours. The mouth of the trailing slug is in nearly constant contact with the tail of the leading slug. Copulation lasts 3.5 to 12 hours, and a portion of the penis (the verge) is inserted into the gonopore and the spermatophore delivered internally (occasionally non-reciprocally). Eggs are deposited in single or multiple clusters over several weeks and hatch in 47-63 days at 14C under laboratory conditions. Captive raised slugs reach sexual maturity in the first year (Leonard and Ovaska, 2002).