Plethodontidae (Lungless Salamanders)_________________________________________________
Four-toed Salamander (Hemidactylium scutatum)
Redback Salamander (Plethodon cinereus)
The Four-toed Salamander is an alert-looking little amphibian that is active from late winter to late fall.  As its name suggests, the number of toes (four, on his hind feet), distinquish it from other salamanders who have five toes on their hind feet.
Four-toed Sally nudged into an unnatural pose to show the ivory belly with black speckling.  Also note "pinch" at base of tail - another characteristic of this salamander.
The tails of Four-toeds are detachable (note constriction at base) and will grow back if they lose it.  It continues to move on it's own, distracting the predator from the more vulnerable parts, namely the salamander itself!  They overwinter underground with others of their kind.
The terrestrial Four-toeds can be found in deciduous forests under rocks and logs.  However, they are usually in close proximity to wet areas.  They prefer to lay their eggs in sphagnum moss along the edges of water.  They are laid singly, and the female will guard them until hatching.
The Redback is our most common salamander.  Like the Four-toed, it is terrestrial, but rainy nights facilitate their migrations.  A study was conducted years ago which concluded that the weight of all of the combined Redbacks in a given area was more than all of the combined birds and about the same as all of the combined small mammals.  That is saying a lot for such a tiny amphibian!
These salamanders are active from late winter to early winter.  I have found them under rocks and logs on
"warm" December afternoons.  They lay their eggs inside rotten logs, and the larvae develop within those eggs, eliminating the need for water, and hatch as miniature versions of the adults.  They overwinter in tunnels and burrows deep under the ground.
There is a gray morph of the Redback Salamander, referred to as "Lead-backed" Salamanders.  I've usually come across populations of either one morph or the other.  Only occasionally do I find them mixed.  There is also a rarer, orange form known as the Erythristic Redback Salamander. 
Erythristic Redback Salamander found in Barkhamstead - photo by John Acorn
"Lead-back" Salamander - a deep gray/brown morph of the Redback Salamander. 

Note - no red stripe down back.