Suminoe no kohama no shijimi ake mo mizu komorite nomi ya koiwatari namu

住吉の粉浜のしじみ開けもみず
隠りてのみや恋ひわたりなむ

Roma-ji: Suminoe no kohama no shijimi ake mo mizu komorite nomi ya koiwatari namu
English Translation: Like the freshwater clams
at Kohama of Suminoe
that will not open,
must I stay shut within myself,
loving on and on in silence?
Meaning: Like the clams on the beach of Kohama at Suminoe that will not open their shells, must I keep my heart shut away and go on loving in secret?
Commentary: Book Six Miscellaneous Poems 997

Headnote: "Six poems from the time of the imperial progress to the Naniwa palace in the third month of spring"
This poem laments whether the poet must go on loving in secret without ever revealing his heart, like the clams of Kohama at Suminoe that keep their shells closed. It is one of six poems from the third month of Tenpyō 6 (734), when Emperor Shōmu made a progress to the Naniwa palace. Among the poems in which members of the retinue sang of the seaside scenery of Naniwa, this one uses the clams of the beach as a preface and sings of a hidden love.
Kohama was part of the shore at Suminoe, thought to be around present-day Kohama in Sumiyoshi Ward, Osaka. Weaving in a local product of the place visited on the progress, the poet likens his longing for someone left behind in the capital to the closed shell of a clam.
A note following the poem says, "The author of the above poem is unknown," and the poet cannot be identified.

The six poems from this one to 1002 form a sequence from the Naniwa progress of Tenpyō 6, in which seaside place names around Naniwa appear one after another: Suminoe, the mountains of Awa, Chinu, Shihatsu, and the shore of Suminoe. "Suminoe" in this poem answers "the shore of Suminoe" in 1002, the last of the sequence, so that Suminoe frames the beginning and end of the series.
The first line, "at Suminoe," is the place name Suminoe in the province of Settsu. It is sung as a famous site near Naniwa, the destination of the progress.
The second line, "the freshwater clams at Kohama," refers to the clams gathered on the beach of Kohama at Suminoe. The first two lines present a local feature of the place visited.
The third line, "that will not open," means "without even opening their shells." It describes the clams keeping their shells shut, and the upper verse up to here serves as a preface leading to the idea of keeping one's heart closed.
The fourth line, "must I stay shut within myself," means "only shutting myself away." The clam closed in its shell overlaps with a lover hiding his feelings from others. "Ya" is an interrogative binding particle that links with "namu" in the final line.
The final line, "loving on and on in silence?" means "will I go on loving?" "Wataru" expresses continuing over time, and the line ends in the attributive "namu" in response to the binding particle "ya" in the fourth line.
Source: Manyoshu
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