1889.] Across the Santa Barbara Channel. 393 
polyorchis, is one of the most common jellyfishes in these 
waters. 
Perhaps the most interesting of all the Medusan denizens 
of the fiords of Santa Cruz is a small Hydromedusa, not larger 
than a small pea, which has this remarkable character. In 
place of clusters of tentacles about the margin of the bell it has 
but a single tentacle placed at the point of junction of the radi- 
al tube and the circular vessel. This single tentacle is a short, 
stiff appendage, exactly similar to one of the four tentacles of 
Dipurena, a genus found at Newport, Rhode Island. It is, in 
fact, as if we had a Dipurena with three of the tentacles miss- 
ing and a single one remaining. In this Californian genus, 
however, there is but one of these curious, club-shaped, stiff 
appendages. A similar genus has never been recorded ; to this 
species I have given the name Microcampana conica. The most 
peculiar structural character is found in the number of radial 
vessels in this jellyfish. All similar Hydromedusaehave but four, 
eight, or more radial tubes. There are some which have six, 
which however are not related to Microcampana, This genus 
has six radial tubes. Moreover, there exists on the apex of 
the bell, as in our Stomatoca, a prominent prolongation or 
projection never seen in Dipurena, its nearest ally. 
There are many other Hydromedusae in these waters, a 
notice of which would prolong this account beyond its limits. 
A huge Sphaeronectes, with a bell a quarter of an inch in 
diameter, a genus never seen before on this or on the 
Atlantic coast of the United States, a beautiful Physophore, 
Diphyes, and a host of others' were found. 
On the return trip to Santa Barbara we sailed through a most 
extraordinary region of the channel in which there is a sub- 
marine petroleum well. The surface for a considerable dis- 
tance is covered with oil, which oozes up from sources below 
the water, and its odor' is very marked. The oil probably 
comes from the upturned asphaltic strata deep below the sea. 
Near the oil well we sent down our dredge and brought up 
a most interesting Polyzoan, an account of which I have al- 
' A full description of these animals with figures will soon be published by me. 
