This single representative of the Gymnoblastea more nearly corresponds to the _T. marina_ described by Torrey, '02. It is, however, much smaller, the erect branches being scarcely ever as much as 15 mm. in length, instead of 30-50 mm. The proximal tentacles are 28 and 29 in number, instead of 22-26, described for _T. marina_. There is very little appearance of annulation of the stem, and no evidence of the "stem increasing in diameter distally." The habitat is also different. _T. marina_ is given as growing "between tides on the lee side of rocks exposed to the breakers of the open sea." The tubularian in question, however, was found only clustered in among the rootlike holdfasts of the _Macrocystis_ at a depth of four to six fathoms. Moreover _T. marina_ is not reported as occurring farther south than Pacific Grove. There seems to be some reason for considering this a new species, but further investigation, and perhaps a study of comparative material, will be necessary to determine its systematic position. CALYPTOBLASTEA Family SERTULARIIDÆ _Sertularella tricuspidata_ (Alder) _Sertularia furcata_ (Trask) Both of the above forms were found on the washed-up holdfasts of _Macrocystis_. Family PLUMULARIIDÆ _Aglaophenia inconspicua_ (Torrey '02) Torrey's description gives "hydrocladia 3-4 mm. long." Out of a large number examined, however, I found none with hydrocladia more than 1.5 mm. _Aglaophenia struthionides_ (Murray) Both _A. inconspicua_ and _A. struthionides_ were taken from the red algæ brought in by the tides. _Plumularia setacea_ (Ellis) This form appears to have a wide variation in its bathymetric distribution. Specimens were collected from the mussels which are uncovered at mid-tide, and from the carapace of _Loxorhynchus grandis_, a deep-sea crab that is only rarely brought to shore by the highest tides. _Plumularia lagenifera_ (Allman) Found on kelp holdfasts. _Antenella avalonia_ (Torrey) Taken in tow-net from floating red algæ. Family CAMPANULARIIDÆ Mention may be made here of one of the Campanulariidæ recently sent me by Professor Hilton of Pomona College, to whom thanks are due for many courtesies. It does not appear to be any species yet reported from this coast. Its identification, or at least an adequate description, must, however, be postponed for a future paper. Summer School at Laguna Beach [Illustration: LAGUNA LABORATORY]