Yes and no. They are actually imperf between, but that is not the terminology one uses with the early revenues. 1st Issue revenues are different in that many types were actually issued as "part perforate" so they are not considered errors, as the equivalent postage stamp would be.
This one is Scott #R13b.
(a = imperforate, b = part perforate, c = perforated, d = silk paper). Not all denominations and types were issued. I have a reference chart on my website here:
http://www.revenue-collector.com/usrevs.shtmlA grayed-out square means that variety was not issued.