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lar arch, derived from the tendons of the latissimus dorsi and connected 
with the deep plane of insertion of the ectopectoral tendon. 
The presence of a third or inferior portion of the coraco-brachialis 
is noted in addition to the upper and middle portion usually present in 
the Lemuroidia. 
The ventral trunk muscles present a distinct carnivore type in their 
arrangement, instanced by the high thoracic extension of the rectus ab- 
dominalis, the occurrence of a well developed supracostalis, the union of 
levator scapulae and serratus magnus, the thoracic extension of the scalenus 
group — interlocking both with the serratus magnus and obliquus ex- 
ternus. 
The aponeurosis of the obliquus externus presents a well developed 
division of the internal pillar of the external abdominal ring, dovetailing 
with the one from the opposite side and forming the triangular ligament 
of the same. 
Mr. H. E. Crampton, jr., reported some of his “Observations upon 
Fertilization in Gasteropods”. 
The observations were made upon the eggs of a species of Doris, 
collected last summer on the Pacific Coast by Mr. Carkms, and upon a 
species of Bulla which deposited eggs at Woods Holl during the months 
of August and September. The results may best be summarized by stating 
that a complete confirmation was obtained of the accounts of fertilization 
given by Wırson and Matuews, Boveri, Hitt for sea-urchins, MEADE on 
Chetopterus, Kostaneckı and WirsyEwskI upon Physa, etc. The sperm 
nucleus is preceded by the divided centrosome, an aster, however, not 
being found till the union of the germ-nuclei. The first polar spindle 
lies at each pole a double centrosome, the second maturation spindle but 
one. These are of great size, however, and the one remaining in the 
egg finally disintegrates, the centrosomes of the first cleavage spindle 
being derived from the sperm. The germ-nuclei do not fuse, but lie very 
close to one another, in contact. 
Mr. N. R. Hazrtneton gave an account of the life history of Ento- 
concha, a molluse parasitic in a Holothurian. His paper was illustrated 
by photographs. 
The following paper was read by title: 
N. R. Haremeron and B. B. Grirrin: “Notes on the Distribution, 
Habits, and Habitat of some Puget Sound Invertebrates”. 
C. L. Bristot, Secretary. 
